I liked the plan of coinciding his signing with the time of their returning to Camp Nou though.
The fans would love the idea as well but I still can't trust these sources completely... Normally I was also hoping to see his jubilee at Barcelona instead of his childhood team Newell's Old Boys or somewhere else. Watching him side by side with Yamal for some games sounds quite interesting. But probably this will stay as a rumour only. I feel like he will end his career in the USA. He already owns the MLS. 
In addition, with the current conditions and with Messi's age now what is expected of Messi about the performance that has decreased dramatically. It's not that he's not great because he's a goat but his prime has run out so why impose it just because of his great popularity.
Maybe indeed the popularity advantage will be able to help Barcelona a little but in the end it will only be enough to cover Messi's salary in the end because when talking about declining performance even though he is one of the recognized GOATs but still his contribution will not be the same as before.