That is not important at all, Mike Tyson was not a likeable character, he didn't smile much and he dominated boxing for years.
My prediction is that Pereira probably winning on points, unless Adesanya make huge surprise with his fighting style and dominates more with wrestling.
I think both of them are good in stand up, Adesanya is faster, Pereira is stronger, but all other skills outside kickboxing is advantage for Adesanya.
I think Adesanya Fans really wanted to see him perform well and surprise the audiences about how he gonna handle this fight. But his problem is Pereira will already know exactly what he gonna do and can predict his movement easily. If Adesanya won't change his fighting style, this upcoming fight will be in favor of Pereira and it might be that the result of this fight is the same as the last one. Pereira can easily dodge and take Adesanya's punches as if it's nothing and that's just how he is always caught by surprise because there wasn't any opponent who can do that against him before. He really needs to win this fight in order to regain back his honor.