Best player to wear an Eagles uniform is without question Reggie White. He was arguably the greatest defensive player in the history of professional football, second only to maybe Lawrence Taylor.
Saquon is a beast we've never seen the likes of before in Philly, but as his career stands now, nobody would say he's the GOAT offensive player in history. He may not even be a top 5 player in his position.
But I would agree he's the best offensive player to ever wear an Eagles jersey in my lifetime. I think he has T.O. beat. It's close though.