Messi has only stayed in the NT because of his name and even his first 2 games were terrible, a brave coach would've benched him like Ronaldo. Granted, he stepped up for the knockouts, any other player would've been riding the bench for the whole tournament like Ronaldo.
Also, Argentina is made around Messi, he is allowed to walk around for most of the game without fear of substitution. His ego is hidden whereas Ronaldo is transparent in that respect. Messi is in the GOAT category, incredible player of course but the guy seems like a dickhead.