It could happen, just lot's of red tape I suppose.
http://www.ladbible.com/entertainment/film-and-tv-there-could-be-an-x-men-and-avengers-crossover-in-the-future-20171107
I loved the first Iron Man, the second one got too goofy for my taste with the third doing a decent job of redeeming things. To me, the first of each of the solo flicks has been the best, Thor, Captian America, Iron Man...I haven't watched any of the TV series, but the movies are very much worth watching IMO. I haven't seen Ragnarok or Black Panther yet but have it on good authority they are both among the best of the bunch. My wife thought Black Panther was incredible.