@strangergirlsforlife um, in my opinion, I liked how the duffer brothers wrote his character this season actually, like in s1 and s2, we've all seen him as a little kid, trying to protect his friends and all but as you can see in s3 and s4, the duffer bros are making his character more mature. And as Finn Wolfhard, himself, said that ,"Mike is growing up and there are some difficulties he has to face when he arrives in California. I think there's some deep down trauma inside his mind, but like, it won't come out." So ig he's just growing up and is struggling to let out his emotions.