I don’t believe his standing as a great would be diminished a single iota because of his personality. I think it’s part of his appeal.
See Zlatan for instance. Even Henry was an egotistical and arrogant person to me on the field. I don’t think very many great players are humble, or aren’t full of themselves. Like y va noted, so long as they have the wins and trophies and records and performances to back it up they will be given their due respect, if not immediately, then in retrospect.
Even here, I remember arguing that Ronaldo was number 1 a few years ago, and receiving some backlash after Messi went out and had a spectacular performance that same day. People saying things like “it’s not even close”... I think a lot of it is the aesthetics of Messi and the ease and efficiency with which he appears to perform his magic. But Ronaldo’s sheer will,goal scoring exploits and ability to step up in crucial moments is admirable as well and I hope when the rivalry is over at the end of their careers we can appreciate them both as two of the greatest players ever, rather than being fixated on who was 1 or 2.