PSG's project looked good at first: plenty of money and they looked like they really wanted to win the Champions League. Of course, there was always a risk that 2022 would be the sell-by date. I'll give you that the French league is meaningless now but so are most of the others. He had to do something special and winning the Champions League repeatedly with an upstart club and/or winning the World Cup could have been something special.
Unfortunately, apart from his first season in France, where he got something close to a goal a game, his stats are nothing special. They're good, but nothing close to a guy who was considered a once-in-a-generation talent. It takes a special mentality to keep on going when you've got everything you want in life. He obviously doesn't have it.