This was not the typical Week 17 situation that a lot of teams find themselves in, which is what makes it worse. It's that they played a game plan, with a bunch of key players, for three quarters and then willingly decided to give up down 3 in the 4th quarter. That's a slap in the face to those players and the game.
That's not the same as sitting your starters in a meaningless Week 17 game to reduce risk of injury. If they'd done that, that's defendable - the game meant nothing. Instead, they put those guys out there (at risk of injury) for three quarters then decided to give up at the end of a close game.
This situation is immeasurably worse for Philadelphia than it is for the Giants. Peterson may have permanently lost the trust of the locker room by doing that - including the starting QB who he used to kick his other QB out the door. Meanwhile, you can bet every player in the Giants organization is willing to run through a wall for Joe Judge after that press conference yesterday. And the Giants lose nothing more than a week of practice and one playoff game they'd almost certainly lose. Not insignificant, but nothing compared to deep fractures across the team.