I see people all over so against it. I wonder if people actually SAW the 21 & 22 Jump Street movies? They very cleverly made fun of the type of movies they were and the fact that they were 21 Jump Street movies. Especially 22 Jump Street, which spent much of it's run time making fun of itself for being a sequel while at the same time doing some of the things it was making fun of. Then at the end made fun of the unending sequels that could come from a successful movie - including parodying cast members being replaced and the like.
Here's a link to a bunch of the posters:
http://collider.com/22-jump-street-sequel-posters/
So I think the idea behind the MIB/Jump Street sequel is to play with the ridiculousness of the concept even further.
Turning it back to Disney - Lord & Miller - the two guys that did these two movies and also the quite brilliant
Lego movie - are on board to direct the Han Solo Star Wars movie. I imagine they will give it a more serious tone than the Jump Street movies, but I am hoping there will be a lot more "fun" to it than we get out of most of the Star Wars movies.