The US has more than 30% of its population on there, the third highest- India has about 20 million of its 1 billion+ people.
It says there are 206 million active Twitter users, 77 million of them in the USA. That’s less than half of them.
Of my family and friends I only know of 2 who use it actively though most have an account.
From my small Eastern European country - no one I know uses Twitter, Reddit is more popular than it. That’s anecdotal, of course.
It's easy to point to 'oppressive' countries like China (where twitter is banned), or Turkey[1], or India[2] as examples of where speech can be severely limited, but there are many limitations to speech in other countries like Germany, Canada, France, Australia, UK.
When you make a globally available website, how do you "follow the law" when the laws of various countries are not compatible with each other? Do you geolock all tweets - Canada twitter is vastly different to US twitter? That doesn't sound scalable good!
[1]: https://www.article19.org/resources/turkey-twitter-becomes-l...
[2]: https://www.theverge.com/2021/7/6/22564768/twitter-india-leg...
Musk's Twitter is certainly going to clash hard with Europe's recently adopted Digital Services Act.