Unrestrained capitalism ruins everything, eventually.
People will continue buying ridiculously priced tickets. Those people will not be the people who've formed the lifeblood of English football. They'll be highly wealthy people from all over the world.
Will this destroy the atmosphere that makes football special? Yes. Will this have a negative impact on Manchester United's finances? No, because there are more "plastic" fans willing to pay extortionate prices than there are "proper" fans who will actually contribute to atmosphere or the club more generally.
None of this should be taken as an attack on foreign supporters or anything similar. I'm Canadian, been to OT 3x at significant travel expense. I'm not the demographic that will be paying the extortionate prices, because I'm not wealthy enough that flying to Europe is something I can regularly do.
The community values of football are entirely at odds with its globalized economics. The money will end up beating the community, because that's how the prevailing economic system operates.