The whole point of section 230 is to let sites moderate user generated content without becoming responsible for what is in that content. What Twitter is doing falls squarely within the letter and the spirit of section 230.
I'm not arguing that X/Twitter is doing something that prevents it from being protected by section 230 as it exists. But, when Congress granted these protections, I think they had in mind things like forum moderation to remove hate speech, not selectively censoring journalists that write critically of a company. So one could rethink whether companies that censor journalists should be protected.