Just like TLJ!
Everything in TLJ had foundation in TFA. Luke’s characterisation was hinted at in TFA, Rey searching for a connection desperately, etc. There was nothing that came about as fact in a major story development beat that affected who the characters were that was ignored or retconned.
I believe he meant Kylo recedes to his status in TLJ of trying to overthrow the big baddie and take his place while doing his bidding, instead of actually moving forward and acting like a “Supreme Leader”.
- Kylo frees himself of the oppression of his Master Snoke, except now he just works for another evil mastermind.
I do feel compelled to point out that Kylo makes it abundantly clear that he’s just using Palpatine for his resources and will almost certainly betray him at the first available opportunity.
Just like TLJ!