Realistically, if you made $400M ($250+M after taxes) would you want to live in Philly if you weren't from there?
The Sixers have already faced this reality, they're better off having their young players bond and keep them than chase free agents.
Machado will end up in LA, SF, Miami, or New York, that's where rich people like to live. He has zero ties to this area, and no reason to think he'd want to live here.
Once a player contract reaches ridiculous levels, you can only buy them if they're so ego driven that they have to max the money (and do you want that player, I want guys who live for the sport, because once they're filthy rich that's the only motivation left, the competitive fire). Most players at that point are thinking lifestyle, family, etc.
Which is why teams like the Phillies have to build from within, Atlanta is smart enough to understand that. You can strategically buy free agents (veteran patches, young late bloomers) but you'll struggle in bidding wars against top talent. Trout is the only player with Philly ties, and he should be the target in 2021.
You can't build a strategy around day dreams.