I’m not sure there’s really any blame to be leveled justifiably. We played him a bit, he looked *okay*, clearly talented but not exactly influential. He didn’t show much to justify retaining him, IMO.
It’s a completely false equivalence to look at his success at PSG and say “oh wow look at what we’re missing”. He’s in a different league, at a club with massively different goals (realistically speaking), a massive talent delta over their domestic peers, and being coached by one of the most sorely overlooked managers in football.
There’s less than zero guarantee that he’d have developed into anything like he has done if he had stayed here.