One of the biggest things to come from the merger of Fox and Disney is that Marvel Studios now has the film rights to the X-Men. With the confirmation that the upcoming Dark Phoenix will be the final chapter of the existing X-Men universe, fans are looking forward to what appears to be the inevitable inclusion of the characters in the Marvel Cinematic Universe. However, as things currently stand in the MCU, we may not be seeing the X-Men anytime soon. According to Marvel chief Kevin Feige, the current plan for the next five years of Marvel movies doesn't include the mutants. According to Feige...
It’ll be a while. It’s all just beginning and the five-year plan that we’ve been working on, we were working on before any of that was set. So really it’s much more, for us, less about specifics of when and where [the X-Men will appear] right now and more just the comfort factor and how nice it is that they’re home. That they’re all back. But it will be a very long time.
Kevin Feige tells i09 that Marvel had been working on plans for the next phase of the MCU long before the deal with Fox was made, and thus, those plans didn't include a place for the X-Men. Feige says that those plans haven't been significantly impacted by this addition, so it likely won't be until after the current plan is finished that new characters, like the X-Men, will be added.
On the one hand, this makes a lot of sense. While we don't have a lot of visibility to what Marvel has planned for its next phase, we can assume a lot of work has been done behind the scenes. A lot of that work would go out the window and need to be started over, all with a much shorter turn around time, if the X-Men were made an immediate concern.
While Marvel has yet to confirm anything officially after Spider-Man: Far From Home comes out this July, we do think we know what's coming. Movies about Black Widow, and The Eternals have been rumored. Sequels for Doctor Strange and Black Panther are expected, and Guardians of the Galaxy Vol 3 is back on the schedule, though it will now be coming out later than previously scheduled.
And there's really no need to bring in the X-Men too soon. There are plenty of other characters that can be focused on in future films and the longer the X-Men are left alone, the easier it will be to bring them back in a new, rebooted, form.
At the same time, as i09 points out, Marvel pivoted pretty quickly once the studio made a deal with Sony to get Spider-Man into the MCU, so it wouldn't be the first time plans had changed because new opportunities had presented themselves. There's always the possibility that, even if there are no specific plans to bring in the X-Men right now, those plans could always change.