He needs something, because he's tied tens of billions of dollars of his own money in an LBO that left him in control of a company with about a billion dollars a year of debt service cost.
I don't need Twitter, since I rarely post on the social, I don't use it for work, and it kind of annoys me too, and if it disappeared I would forget about its existence in two weeks, like I forget about my favorite podcast three days after they started their 3-week summer vacation.
I don't need to go to the gym, but I have been going for about 30 years. If they forced me to spend an extra $8 a month, maybe I would move to another gym where I pay less, but how ridiculous would my statement be, "I don't need the gym, bye"?
Stephen King doesn't need Twitter to publicize his work, and he doesn't even need to work, since he seems to be quite well off. But most celebrities -- "most" is vague, I know -- live to be the center of attention, to be heard, to be considered. And a few years ago the platform was Facebook, then Twitter, after Trump's election, became more and more the place to be if you want to participate in the "discourse."
King needs Twitter now or another platform now or in the future because, apparently, he needs to be heard, to be part of the conversation, to have his old man criticisms heard. But now that platform is Twitter.
On a similar note I feel like Elon is the Ultimate Tweeter in the sense of validation (and amount of validation) he seems to get from posting. I've been wondering if it colored his perception of how the average person interacts with Twitter.