TLJ is not a perfect film but Abrams has absolutely no room to talk here. His film is responsible for the stagnant worldbuilding with no creativity, a cliffhanger ending that forces a sequel occurring immediately afterwards, multiple "mystery boxes" that must be resolved that even he had no answers for, and various uncreative setups with no resolutions that all need to be paid off, putting Johnson into an impossible position for a follow-up.
These movies were doomed from the moment they decided to rehash the Rebels-vs-Empire conflict and destroy Luke's Jedi Order.
TLJ had by far the smoothest production of any Star Wars film under Disney. That more than anything else is why Kennedy wanted Johnson back.
JJ did not force a direct followup, you absolutely could have done a substantial time skip of years even. You did not need to pick up directly where TFA left off wothRry meeting Luke.
The issue is that middle films are exactly where you want to be adding planks to and fleshing out your story.
This was something that was already needed more so than usual coming off of TFA.
And instead of doing that, TLJ ended up doing the exact opposite. Worse yet it was a poorly charted deconstruction that then only tepidly
walked back from the implications of its own method, leaving the setup flattened from where it was before.
It also doubled down on bad elements from TFA such and poor worldbuilding, issues with characters such as Finn, and did nothing to move the actual story forward. Not only that but all of the B plots were either unecessary or retreads of TFA with at best insufficient gradation to justify largely repeating from the prior film.
TFA is not perfect, but the mystery boxes weren't going nowhere, things like Rey's parentage were clearly setup to go in a certain direction and TLJ doesn't spend remotely enough time on 'your parents we're actually nobodies'to make that anything other than a take backsies.