The problem is they have no leverage since Disney can still use the characters outside of a Hulk movie and we're getting a She-Hulk show with no mention of Universal and Disney having done a deal to making it happen. So if they can have Ruffalo in the movies as hulk, in a She-Hulk show as Hulk (along with She-Hulk's origins), and possibly Thunderbolt Ross turning into Red Hulk if they go that route.... it's just like, yeah Universal has a history and technically a contract for distribution, but Marvel doesn't need Universal in any way.
She-Hulk got approved but don't be so sure Universal isn't involved. Universal sold television rights to the Hulk to New World Television in 1988 with the caveat they would have some level of participation. Who owned New World Television? Answer: Fox. So unless all contracts in past are null and void, Universal is entitled to participation.