I don't think Messi has underperformed in PSG. Considering his age, he has contributed immensely to the success of the club. The only reason why the fans or management thinks that he has not done enough was that they failed to win the Champions League this season. The club would have been singing praise songs about him if they had been crown the champions of Europe.
After Messi came to PSG, the club has been knocked out of the Champions League in the 1/8 final for two years in a row, and Messi himself plays in stealth mode in important games. By the way, there are also two departures from the French Cup in 1/8 in a row. I do not think that such a result was expected from such a promoted player as Messi. It's clear that football is a team game, but it just so happened that when a team plays well, it becomes Messi's merit, and when it's bad, it's not his fault. But for some reason PSG fans don't want to eat that shit, hehe.
When something that is expected cannot be obtained, disappointment will make fans forget about the good performance that has been contributed to the team. PSG elimination from the Champions League is not just this time, Barcelona once got rid of PSG dramatically after suffering a 4-0 defeat in the first leg, in the next game Barcelona managed to beat PSG with a score of 6-1.
The performance of the players cannot be completely blamed, the coach must be a gentleman with the bad results achieved by the team. Players labeled Stars will always be the main target for the failure of their team in a competition. Messi's decision to leave PSG was correct, if in the following season PSG can win the UCL trophy, it means that PSG bad luck is purely because of Messi presence in their squad.