I’m sorry, but do you have direct example of this?
I remember inconsistency, not pouting and bad attitude
It's up to interpretation right (it's why this argument is here in the first place) but to me it's his behavior on the bench. I can try to find it but there are pictures where the whole team is almost falling over the bench (I guess end of game or serious chance) looking down one way, Perlini is staring into the abyss infront of him. On the ice he looks to make plays for himself, he doesn't engage with his body even though he has great physical gifts. He was scratched and had to have been given multiple chance by JC to get it together; he provides little to absolute zero off the puck game (again great tools). Never seen him give energy out there which a lot of the lesser well rounded players at least know to provide. Inconsistency and below average hockey IQ can, in my opinion be attributed to an entitled personality (he can think it's below him to scrap for every little inch - just one example).
While negotiating for his new contract there were reports he was looking for a grossly higher amount than what was consensus for him, he held out longer than most of our guys. He was already moved from the team that drafted him and is regarded league wide as a guy that still hasn't out it together. Arizona fans echo these sentiments.
Look, one by one these things aren't conclusive to any characteristic or personality traits. But add them all up and it's super easy to come to conclusions like he's entitled, he's more of a selfish player etc. I dont hate he stayed on the team for now, but for sure he's not my favorite player at all - and it's mostly because of his attitude.