Of course, Disney (with the rights) could go in a completely different direction and recast all of those characters. That would probably be best anyway because the X-Men have been through a number of similar plots to the point that I have X-Men fatigue. Fatigue isn't good for long franchises, and it takes a real effort to breathe life back into them. Marvel proved it could totally do that with Spider-Man so maybe it can totally do it with X-Men as well. They just need to have really good casting and good writing and lean on the characters in the greater MCU that remain popular with fans.
Also, Disney should negotiate new contracts with Downey, Evans, and Helmsworth...those guys are pure gold when playing the now iconic characters we've seen them in for some ten years now. If you haven't seen the trailer yet for Dark Phoenix, it may be worth a look. I've included it below for you. It may actually be good too, but to make Dark Phoenix truly worthy it should involve a huge universe as big as the Avengers movies. Dark Phoenix destroys suns like they were pieces of candy and can melt Professor X's brain like he was a drooling idiot with a sippy cup. She is power incarnate and all of the villains we've seen in the X-Men are nothing compared to what she eventually becomes. Knowing all this makes me feel like there hasn't been enough build-up to this to feel truly earned. Seeing Jean Grey give off some light here and there and some foreshadowing of the crisis of this dark side to her soul just hasn't been satisfying enough for me to declare: we are ready.
So yeah...it seems like a money grab. But that's what studios do sometimes. It takes a truly disciplined hand to play it slow. After all is said and done, Disney has played a slow hand for years and has shown remarkable discipline and restraint to just allow all these stories it's been seeding to converge in the unrivaled spectacle of Thanos unleashed. Warner Brothers (the DC universe) and Fox (the ones who used to own X-Men) just never seemed to get that. They were always too rushed to keep putting out product with no regard as to whether it ever made sense with anything that had been released before by any other director.
At least Snyder's soft reboot seemed to make sense now and pave the way for Dark Phoenix to have a decent chance at being good. I much prefer the new cast to the old cast, although I kind of miss Patrick Stewart. He was a perfect Professor X.