The problem is Commander is a bad format, especially when it's catered to. I actually liked playing Commander back when it was still new, because there wasn't really a meta game and it was just a chance to run some bad cards or strategies against a table of people doing that. Then people started having very refined decks and I just didn't care because the randomness of draw becomes cumbersome or it just devolves into functional reprints plus tutors which just makes it a bad Vintage format. Then the introduced Commander products and leaned into the functional reprints and tools for certain strategies which destroyed the format even more.
As for why white is bad in Commander, I'd say it's that there isn't a ton of functional reprints for things like Thalia, Land Tax, etc, so they're still playing an old style of Commander deck while other colors get far more options in terms of functional reprints. The only thing White has in mass is mass removal, which is fine but not a winning strategy. I guess they have anthems too, but when there are multiple players and so much removal it's hard to play a weenie deck in a naturally slower format, and good spot removal isn't great when there are multiple players playing bomb creatures.
Now moving on, I fucking hate Arena, as I just saw some Alchemy Cards and thought they were a bad joke. I'd post them but Image server is down so here's the text:
Molten Impact 1R
Sorcery
Molten Impact Deals 4 damage to target creature or planeswalker. If excess damage was dealt this way, when you cast your next instant or sorcery spell, Molten Impact deals damage equal to the excess to target creature or planeswalker.
It's not a super powerful card, but holy shit is that wording is obnoxious and if you're going to have to write something so convoluted, you're better off not doing it. This is the worst part about digital products, they actually have less complexity as the game does a lot of handholding and you can't bluff as easily, which is fine as something gets lost in translation, but then the idiots lean into the design space and make retarded shit like that. Or worse they make black boxes like:
Imperial Blademaster 1RW
creature - Human Samurai
Double Strike
Whenever a Samurai or Warrior you control attacks alone, draft a card from Imperial Blademaster's spellbook.
2/2
Fuck this type of card style that as far as I know sprung out of Hearthstone and unless you've looked it up on a third party site you have no idea what cards that ability generates. And looking it up it's a list of something like 16 cards, why? I get you're trying to create something that makes games more dynamic, but most of the time this shit doesn't, it just makes you either really happy you got what you wanted or annoyed you got garbage. It also doesn't really make you think that much because most of the time I ran a discover card in Hearthstone I pretty much knew the answer right away in terms of what to pick because you generally have some idea of what you're playing against, what's in your deck, and what you may be lacking with what's in your hand.
Either figure out how to make a game fun without this digital bullshit design space or just go apply to work at Blizzard, where you might get diddled but they love this retarded shit.