Why doesn't Blizzard just delete/ban cards?

In Magic or Yu-Gi-Oh, there have been banned cards in some formats. My question is, why don't you do that with Hearthstone? We've seen cards deemed as "cancer", such as Baku the Mooneater. There probably is some easy reason to this that someone already answered, but it would seem hella lot easier to just delete the card together, refund the dust, or move it into another format, like a format where every card is available(No, not Wild, we would move Baku OUT of the Wild and into this "fun" format). I am not salty about all these Odd paladins or Odd Rogues, because frankly I believe there will always be a deck everyone hates and right now it's a combination of Odd Paladin and Big Priest. I'm not that miffed by Mage because it's they're turn to shine. So why?

Magic and Yugioh don't have the option to errata a card as easily as Hearthstone does.

In theory, no Hearthstone card would ever need to be banned because it can just be changed to no longer be a problem, and unlike with physical card games there's no old copies of the broken version in circulation because everyone's cards change.

Wild is the place for the incredibly powerful combos to exist. That was why it was created. Would it be great if Hearthstone had more formats? Sure. I just don't know how well a format where you - to use your example - ban Baku the Mooneater would do. Presumably you'd also ban other cards, but at what point do you stop? Do you just ban a few new cards every few months when people complain about the deck which inevitably rises to the top of the pack? Would cards ever be unbanned?

I'd personally prefer a rotating sets format, akin to what they're doing with Arena. A new subset of the game available every month, so the format can never get too stale. They can even remove Witchwood, Karazhan and Frozen Throne for the first month.

So.. You want wild wild? 

Wild is the "fun" format.

They really need to delete big priest altogether

What they need is to leave Wild as it is, but just create a third format that's about mid-tier.  A sort of "Limited" format.  In other words, take the new way that Arena's card pool is set up.  Make a constructed format that has that same card pool!  Maybe give out some Wild packs as monthly rewards for playing that mode to allow players to grow their Wild collection if they want, especially if a newer player wants to get some older cards.  And in this format they could straight up ban certain cards from being allowed to avoid specific decks from being super OP.

If Blizzard started deleting cards to remove cancerous archetypes, another type of deck would just rise up to take the place as the current cancer deck.  So then you'd have to complain about that deck, get more cards deleted, complain about the next new cancer deck, get that one deleted, etc etc, until every card in the game is deleted.  So if that's the solution you really want, you could just delete the game from your computer instead.  Much faster solution than petitioning Blizzard to fix/remove cards.

Quote From ShadowsOfSense

I'd personally prefer a rotating sets format, akin to what they're doing with Arena. A new subset of the game available every month, so the format can never get too stale. They can even remove Witchwood, Karazhan and Frozen Throne for the first month.

That's really unfriendly to new players, though. You basically need to have a reasonable number of cards from every single set in order to stay relevant in every meta. Currently, there's a solid understanding of which cards are most relevant to own for people with limited dust (the ones from the current year). If you make things go nebulous, no one but the most dedicated players are going to stay around.

I'd be okay with rotating Classic cards, but only in the case where they create 100+ new cards to swap in instead of pulling directly from old sets, to reduce that immaterial feeling as much as possible. They can even be reprints of old Wild cards, they just need to feel separate.

Quote From MurlocAggroB

Quote From ShadowsOfSense

I'd personally prefer a rotating sets format, akin to what they're doing with Arena. A new subset of the game available every month, so the format can never get too stale. They can even remove Witchwood, Karazhan and Frozen Throne for the first month.

That's really unfriendly to new players, though. You basically need to have a reasonable number of cards from every single set in order to stay relevant in every meta. Currently, there's a solid understanding of which cards are most relevant to own for people with limited dust (the ones from the current year). If you make things go nebulous, no one but the most dedicated players are going to stay around.

I'd be okay with rotating Classic cards, but only in the case where they create 100+ new cards to swap in instead of pulling directly from old sets, to reduce that immaterial feeling as much as possible. They can even be reprints of old Wild cards, they just need to feel separate.

Well yeah, obviously. I mean, this mode would be ridiculous anyway, there'd be no point in trying to balance it if the decks will all just change every month, so some months it could be wildly imbalanced and some months it'd just be really normal.

I'm not suggesting removing Classic or Wild, just having this other mode in addition, as like a dumb fun mode.

Well, that's kinda the point of the Brawl Block tavern brawls. It's probably fine staying in that format.

I was a semi-hardcore Yu-Gi-Oh player for many years. One thing I really enjoyed about the game was that I could switch back and forth between a banned list format and non-banned list format as I saw fit. Tired of Chaos Control? You could join an official tournament and play against other decks. Wanted to play with your friends or even have an unoffical tournament in your neighborhood rocking that nostalgic Chaos Goat Control you could do that too. Whenever you wanted to you still owned your cards and could come back to any hardcore or meme homebrew decks you put together whenever you wanted. 

In HS this is not the case due to how digital card games work. You change something too drastically and you essentially do delete a card or deck from the game. Some things can only be balance tweaked before you simply break them and they no longer work anywhere close to how the synergies worked before the changes. You have no option to keep 'your' cards and play them just in private games with friends. So the thought of suggesting changing more cards in wild, or even flat out deleting cards, reeks of something no less than disgusting to me. My biggest joy about card games is being able to save cards & decks for however long you want, whether they were Tier 1 decks or sub-par 10% WR memes, and come back to enjoy them after however long of a break you took. Having a sense of real longevity in your cards created that. It also established a sense of consistency (In the sense that you could depend on your collection more or less still being there months or years down the line). Massive over-the-board pendulum nerfs or flat out card deletions strips away such a sense of consistency and for many players it would make them care about the game less. After all, if most of your favorite cards aren't even safe from complaints from bored players wanting a change even in wild, resulting in major breakings of card synergies or card deletions, then why should you care about your cards.

Grinding out gold & dust, and spending hard earned real money on cards, becomes massively less appealing if most of your cards/decks in eternal formats (which wild is supposed to be) do not stand the test of time to do frequent overhauls on what synergies are deemed worthy by vocal minority. I know I would never have switched from a f2p player to a paying supporting customer after so many years if my cards could just get deleted, banned from all formats (even wild), or turned into post nerf rofl-copter Warsong Commanders so easily.