Maybe there will be a way to do a 2 in 1 edit with this and TROS to make a better Episode IX, or replace IX completely.
I had a similar thought. A 16 year time gap from TLJ to this wouldn’t be completely unprecedented. Episodes 1 to 2 have 10 years, for example. If you removed TROS, you’d just need the crawl for the new movie to do the heavy lifting. Something about the First Order getting toppled thanks to Luke’s final stand.
The biggest problem for a 2 in 1 would be giving a satisfying finish to Kylo Ren. And obviously the First Order wouldn’t exist in this new film. Maybe you could cut all of Palps out of IX, and use some AI dialogue to have the characters be after something else. Let the film play out all the way to Rey and Kylo’s duel on Exegol and his redemption. Then we could have Rey go to Ahch-To, but instead of having her go to Exegol to defeat Palpatine (who wouldn’t exist in this edit), we would use footage from this new movie intercut with the TROS finale. Idk, I’m just spitballing.
Yeah a lot will depend on what actually happens in the movie. The long gap might not be so obvious/explicit. The real issue will be Kylo/the First Order, you could argue TLJ provides decent wrap ups for Poe and Finn.
Ultimately the simplest solution might just be using a scene to swap in for a new ending.