He does not need to do these things but he loves doing this. It does not help his career and only increases hate in fan community against him. Except if you are a fan of Halaand and a loyal fan of Manchester City, it's hard to accept or support these activities. Haaland does not need to do this to show that he is strong and manly. Playing fairly and beating the opponents are things he needs to focus on.
Haaland should be punished for disrespecting a manager in the way he did. Speaking can be accepted but touching manager like he is your mate in such a disrespectful manner should not be welcomed. If it was in previous seasons that there were better aggressive players, Haaland would not have walked out of the pitch without getting some heat from the Manchester city players. Gabriel Jesus that tried to say something was still belittle by Haaland because he is very arrogant and rude but he should watch out because there are some managers that if he does what he did to them, he will not be ignored. Arteta worked with Haaland before so maybe there is some little friendship between them therefore that made Arteta to not take the issue serious and also he is a silent individual that does not like problem.