Yes and no. Yes, in the sense that Marvel are now no longer restricted by pesky rights issues and they could finally make a good FF film, and do a movie about the X-Men that’s closer to the spirit of the source material.
But no, in the sense that Marvel wasn’t as experimental as Fox was with their comic book movies, and with Fox being gone that actually risks the genre becoming a little too homogenous and stale. Marvel Studios would’ve never have made an R-rated Unforgiven-inspired Wolverine movie, nor would’ve they have made a raunchy R-rated Deadpool movie.
Deadpool, especially, felt like a fresh breath of air from the usual superhero fare in that it smartly poked fun at the genre and its tropes that had become tired at that point. Marvel Studios is more consistent than Fox, sure, but Fox was the one studio that was really trying to push the envelope for what you can do with the genre. With Fox being gone, along the Netflix Marvel Universe essentially defunct, if it weren’t for the Sony-verse movies as well as the DC films then all we’d be left with are the family-friendly MCU proper movies and shows.
Which I think is a problem for me. DC in comparison has more variety. In DC, they can release an R-rated stand-alone Joker movie in the same time year as their PG-13 family friendly Shazam movie and no one blinks an eye. Marvel Studios can’t do that, and aren’t interested in doing R-rated movies besides DP. So there is both good and bad aspects to Marvel gaining control of all their characters.