I think Messi will not go anywhere. ~~~ Plus Messi will age one year and hardly anyone will need it as a player, although his name will still work for marketing.
Who knows? You must know that age isn't a big problem if the player still can take advantage of the team. Even if Messi will age one year more, I am pretty sure that the interest from other clubs won't disappear. Look at Zlatan Ibrahimović, he was already more than 35 years old but AC Milan still bought him on the previous transfer season (Jan 2, 2020). As long as Messi has no problem with his physical health, then there is always a chance for him to move.
If Messi leaves for Milan, Inter or Juventus, he may be able to show something. But then he will have to say goodbye to the dream of winning the Champions League once again. Agree that Italian clubs in the next couple of years cannot claim victory in the Champions League. But Messi wants to move to Manchester City in a league where physical strength is the main ingredient for any player. Can Messi keep up with the pace of the English championship? I doubt it.