Abrams was an interesting (read: poor) choice for the final film, because he's famous for setting up compelling plots and not sticking the landing. See: Lost. His whole "mystery box" thing is great at pulling in viewers, but he's never been able to come up with something that works when he's forced to finally open the box.

Amusing juxtaposition in critical reception:

Article about his mystery box thing before Rise: https://www.success.com/jj-abrams-and-the-unopened-mystery-b...

Article about his mystery box thing after Rise: https://screenrant.com/star-wars-rise-skywalker-abrams-myste...