Before I begin, I am a "Kylo hater" ... but i think I can offer up more objective and less passionate arguments than I usually do to explain some of my hypotheses or objections.
I can't imagine having Adam Driver in your movie and thinking it's okay to not give him any lines after he makes this huge shift in character.
The more I think about it, the more I think we were robbed of so much good Kylo material after his turn. If he was taken by Finn and Poe after his fight with Rey, we could have had so many great interactions with the major cast.
I think Ben's limited screentime post-turn is fundamentally because... he's the last Skywalker that everyone buys into.
As such, he's way too big to share the screen with a Rey Palaptine who's unrelated to the Skywalkers, been deprived of the capacity for major scenes with Fisher due to her tragic death, and suffering from a schizophrenic story-arc that is also likely trying to compensate for the perceived weaknesses or Rey Random in "The Skywalker Saga."
I mean, think about this: barely anything really new was conveyed about Kylo/Ben's past once the brief mention of Palaptine whispering in his head was mentioned, Ben Solo was given a monosyllabic script with an onomatopoeia instead of a word, and the character still had limited screentime... and yet there's a bunch of people, critics and fans alike, who still feel he overshadowed Rey.
That's
not just the product of Adam Driver's talent. He's freakishly good, but the role is actually somewhat limited compared to his full skill set.
That's also very much, and in my opinion even
mostly, the simple inadequacy of Rey's three film story-arc, which until TROS changes it, is supposed to be unconnected to the Skywalker family drama the series has at its heart (which Kylo has) and which has no real momentum or major character challenege left over form TLJ either (since that was more Luke's film than hers).
I think Abrams and Terio limited what Ben Solo did because they didn't think they could adequately make Rey stand out as the lead while still following even a hint of TLJ's creative philosophy *and* have Ben Solo get a redemption - which apparently had been ordered form on high in LFL and was the main reason Palpatine came back. Rey Palpatine is what happens when someone feels that Rey Random will get overshaowed by Ben Solo getting redeemed, but doesn't have the balls to go Rey Skywalker because that's too
blatant a rejection of TLJ.
Even before including Driver's talents, a Skywalker grand-kid having a redemption story and bringing in the weight of his entire family story behind him is already a "threat" to character who's not part of that family.
Rey and Kylo do not have a reciprocal character relationship - the way TLJ set them up, one can only rise at the others' expense in some way or another.
Kylo was the most interesting character in the ST.
They did everything they could to promote Poe, Finn and Rey as the next generation Han, Luke and Leia. It didn't work.
Not only did they kill off the last true Skywalker, they replaced him with Palpatine's granddaughter.
I am honestly stunned at what they've done. I'll never be able to watch any of the other films in the Skywalker saga again. Knowing that ultimately Palpatine succeeds in erasing Anakin's entire family line.....
Nope. Too depressing. All the hate directed at Rian Johnson should be reserved for this. Sorry.
I have to vehemently disagree that "They did everything they could to promote "Poe, finn, and Rey as the next generation Han, Luke and Leia.
If they did, Rey would be a Skywalker or Solo, Finn would probably have been a Jedi or revolutionary (as Trevorrow's script made him), and that would be a more likely kiss to take place than Rey and Kylo. And if they were neglecting Kylo, he wouldn't be the main mascot for TFA, and still a huge presence always equal to Rey in TROS and TLJ's marketing, the only character to share more Han Solo screentime post-TFA, and we wouldn't be seeing Finn slide further and further back.
Was it scummy to kill the last Skywalker? Yeah. But Kylo only really got redeemed because he was the last Skywlaker; some fans considered them screwed the second Kylo lost Rey as a possible alternative legacy character peer.
I honestly think his story would have been better and his survival would have been more likely with Rey Skywalker; less pressure on him from any direction, and less of an uneven and parasitic relationship with Rey.