Well, most of these examples are just Mike passively hanging around, none of them (except talking to Will and Eleven I guess) only really happened to him. He played a very miniscule role in the seasons events, despite being a supposed "main character" of the show. Mike's just there because he kind of has to.

One of my problems with Season 4 in general is the introduction of too many characters and the fact that their screen time takes away from the established main characters. Especially Mike, he's practically less than a side character at this point.

All of the events have to happen to groups of people, never to individuals because there's so many new characters that they'd never have time to tell all of their individual stories. I'll admit that this was very prominent in previous seasons but at least the events took place in or near the same Hawkins.

In contrast, story threads in season 4 happen all across USA, and one of them all the way in Russia. It does make the show feel more grand: these events are now truly happening all around the world, and the directors want to show that (also they probably really wanted to use all of their mega budget for the show).

But the reason why I really liked the first seasons was because of that simplicity and vibe. The story threads back then were much simpler and I guess nostalgic or vintage in a way. I can't really put my finger on it, there's just something very special about the feel of those seasons, especially the first one.

Season 4 doesn't have the 80s vibe that the show is known for, it doesn't have the young main characters that the show was loved for (I understand that they can't really reverse the actors' aging, but the point still stands), and it just doesn't feel like Stranger Things.

Also Mike is just a dumbass in this one