Messi can play well till his fourties if he want but I am not sure he will play well in Premier League after his 35s.
I doubt if he will play till forties. 38 may be the last age for him to play in a football match. But it is purely our speculation, we don't know what he already plans for his career in the old age. But I disagree to underestimate him to play in Premier League. Never judge that he won't play well till he tries to play there for one season at least.
In top leagues a player playing to forty plus years is unheard of, goal keepers can -buffon- let's not run the time/age limits of Messi playing football. There are other things that can stop or put to end the professional playing football career of a player
+ Injuries and reoccurring effect of surgeries
+ Club/personal/families-this mostly family opinion- the club/personal can be problems.
Even the players want to keep playing these and more can make them have a changed heart
You're completely right. Although Messi's manager was his father but he was the one that makes Messi have a change of heart when he decided to move to Man United due to the problematic false allegation said about him by the club board despite all his commitment to the club.