Rian Johnson foi considerado para o episódio IX?

De acordo com Johnson, foi "nunca nos cartões".

Isso, para ele, parecia ser "sempre o plano", e ele acabou de sair para trabalhar na nova trilogia que ele havia lançado e que deveria ser dirigida.

It was never in the cards. It was always the plan for me to do this, and then hand it off to the next director, whoever that was going to be. So, I never had that really in my head, and now I'm just really excited about the next trilogy.
_{Cinema Blend - How close Rian Johnson really came to directing Star Wars Episode 9}

De acordo com o artigo do Slash Film , o repórter de Hollywood conversou com Rian e perguntou-lhe sobre o episódio IX recebendo a seguinte resposta.

J.J. Abrams is doing a third movie. I’m not involved in it. They’ll be writing their own story but continuing on with what we did.
_{The Hollywood Reporter - Interview with Rian Johnson}

Em uma declaração que ele fez em setembro, ele segue o mesmo sentimento

“It was never in the plan for me to direct Episode 9, so I don’t know what’s going to happen with it… for me, I was entirely focused on Episode 8 and having this experience. Now I’m just thinking about putting the movie out there and seeing how audiences respond to it. So no, I’m not really thinking about that right now. Whoever does it, I’m going to be really excited to be an audience member again, and to sit down and see what the next filmmaker has to show us and where this story ends up going.”

JJ Abrams foi anunciado no dia 12 de setembro de 2017 para voltar a reprise do papel de escritor e diretor do Episódio IX

With The Force Awakens, J.J. delivered everything we could have possibly hoped for, and I am so excited that he is coming back to close out this trilogy
_{Kathleen Kennedy - StarWars.com}

De acordo com o este artigo sobre abutres , a razão para a partida de Trevorrow foi devido a diferenças criativas / diferenças pessoais com Kathleen Kennedy. Suportado por este artigo no StarWars.com (desculpas pela linguagem frutífera) )

“There’s one gatekeeper when it comes to Star Wars and it’s Kathleen Kennedy,” says a veteran movie producer, who has worked with the studio chief. “If you rub Kathleen Kennedy the wrong way — in any way — you’re out. You’re done. A lot of these young, new directors want to come in and say, ‘I want to do this. I want to do that.’ A lot of these guys — Lord and Miller, Colin Trevorrow — got very rich, very fast and believed a lot of their own hype. And they don’t want to play by the rules. They want to do shit differently. And Kathleen Kennedy isn’t going to fuck around with that.”
_{Vulture - Colin Trevorrow’s Firing From Star Wars Is Another Reminder That No Director Will Ever Be Bigger Than the Franchise}

CinemaBlend - Rian Trilogia de Johnson Star Wars