That's just drama talk. It doesn't matter what he's "meant" to be, it's what he can do in circumstances. I've seen many veterans nearing their 40s being subs and making impact, when subbed on. Examples like Totti or Joaquin. They also were protagonists in their youth, but accepted the role of impact subs and daddy-in- the-locker room role fine. Think Messi could do this too. His ego isn't as inflated as Crynaldos
Totti literally retired from his NT aged 30, after the WC win
And Joaquin is just a bad example, he is nowhere near that level of fame and impact on the team.
Almost all legends of the game retired as starters, either really at their peak or because they overstayed their welcome.
Zidane retired after the 2006 WC
Pele retired one year after the 1970 WC (he was old (31) for the time, but surely he could still contribute if he wanted)
Maradona stayed too long, but was still a starter (until he was banned
)
Cruyff did not even play in the 1978 WC
CR prefers to fire coaches and drag his team down instead of coming in as a sub
Beckenbauer retired after the 1976 Euros while being selected in the team of the tournament
Xavi retired from the NT the moment he saw he was not a starter anymore
Iniesta also left the team after being a starter in the 2018 WC
And the list goes on and on. There are also cases like R9, Ronaldinho etc, who were dropped from the NT because they declined massively. Who knows, maybe they said that they would not accept being subs behind closed doors.
So, this is no „drama talk“, this is a pattern that repeats itself again and again. Who knows, maybe Messi decides to take a smaller role, but so far it seems that he would like to retire from the NT while still being their best player (though inarguably years past his prime).