Because this isn't really about building a neat social network, it's about power. People have tried to do what you said. Let's make a Twitter that's not contro

Because this isn't really about building a neat social network, it's about power. People have tried to do what you said. Let's make a Twitter that's not controlled by the hard left! The result was Twitter's ideological allies at tech firms immediately banned them from every platform they controlled, and other allies ganged up to hack and destroy them. You cannot start a Twitter competitor today, it's impossible, because: 1. The sort of people who found companies tend to be pro-free speech because their economic survival depends on having risky but correct ideas, and that naturally leads to a sympathy for free speech. 2. The sort of people who hate free speech are obsessed with Twitter/tweeting platforms specifically. 3. They are exceptionally aggressive. They will do anything, including damaging their own companies and even breaking the law in order to stop any other platform from becoming popular. They've managed to take over tech firms to a sufficient extent that they will destroy any attempts to replace Twitter, which they see as a key pivot point in their power over society. The obvious solution: buy Twitter and fix it. It's too big to ban. This also has the major benefit of really, really upsetting Musk's ideological enemies. They'd hate him anyway and many are in powerful positions in politics and the media. Even the thought of losing Twitter to Musk has very conspicuously driven them into a frenzy in recent days, and such frenzies discredit them in the eyes of the general public, thus weakening their ability to move against Musk.