No one should pay more than $100, that number lets you build your collection, enjoy the game and complete your daily quests, you can go under that an grind bit more, but IME you really shouldn´t go higher than that.
Spending $0 needs to be a viable option.
I'm not going to assume your opinion either way on this issue, but I am damn sure that at least when it comes to the MTG:A subreddit community, the people who like this game's economy fundamentally don't understand the idea that people need to be able to play, competitively, for completely free within a month's worth of grinding. That's just the expected bar for a F2P player to be able to play a game for free.
And you need F2P players to play the game so people who spend money have someone to play against. That is the fundamental basis of the entire model.
And all the dumbasses posting threads along the lines of "Look How Amazing Quick Constructed is to grind" don't seem to understand that they are doing above average and casual
bad players you still
need will not be doing that well in those settings. They also don't understand how much the next wipe is going to negatively affect that environment. And frankly they are going to get what they deserve when this game does bad and they don't understand why.
And yes, saying "**** all the free to play peasants" is an option, but that's not how you get a new market share. That's how you split your old market share, maybe get a few long-time fans back into the game, and overall have the game end up as just another niche product like MTGO.