As a fan of Musk and his companies, I personally hope this fails. He's already busy enough running SpaceX and Tesla which matter significantly more to the future of humanity than a website that lets people type 280 characters.
Long after people land on Mars and spread to the farthest reaches of the solar system, humans will still be social creatures, and thus there will be social media.
All of mankind’s achievements and technological advancements eventually culminate in more social media.
Social media, especially in a narrow sense (e.g. Facebook and Twitter are "social media", forums and chat programs are not) is not necessary for humans to interact. Nor is the current model of social media - with "influencers", viral content, and a strong incentive for performative interaction - necessarily the best one for society.
Internet communication has value to humanity. I'm not so sure that's true about social media as it exists today.
