I thought EDH would satisfy my casual interest in MTG. But it ended up being worse than competitive play because of politics, vague deck building restrictions for balance(brackets) and difficult to organize people to play.
I settled into boardgames(especially solo boardgames) last year to satisfy that itch.
I see at least 2 reasons why we don't see proxy play in MTG.
One is the strong dependence on your peers for approval. If your group is against proxies, then you are screwed.
Second is that there are now more ways to play against each other online for free. This approach is much more convenient compared to creating proxies IRL and allows you to play with other people outside your peer group.