Couturier, Giroux, Laughton, all predate the current development priorities put in place by Hextall and kept ever since. Even then, they handled Couturier atrociously and did nothing to grow his offensive game. He succeeded despite them.
They absolutely blew Schenn. A player they couldn't figure out and who got it together when he left.
Hart, sure. I guess. Goalies are luck and voodoo.
Ghost and TK have both been pretty open about how they got better once they started ignoring what the team was telling them to do, so that's the opposite of good development. They had no idea what to do with Ghost the whole time he was here.
Sanheim is a development disaster. The franchise had even less of an idea of what to do with him than Ghost. They did their best to trade him and lucked into failing. Who knows what he could be has they put him in position to succeed like they did with Provorov.
Zamula is a development failure. His handling has been disgraceful.
The Flyers despise offensive hockey. Michkov does not need the Flyers telling him to stop being "cute." Or to stop playing a possession game. Or to slow down. Or to focus on defense over scoring. All things they've told players, and punished them for. Michkov already knows more about winning hockey in 2023 than everybody in this front office combined. There is nothing of value any of them can tell him. You don't get to where the Flyers have been by being good at development and evaluation. You get the by being very bad at those things.