In my opinion, staying on X/Twitter is a political act.
It is an advertising platform. The advertisers need an audience. The audience needs content. The posters are providing that content (free of charge). Without an audience, there would be no advertisers, and Musk would not profit.
Musk is using the platform to stir up racism and incite racist violence. To use X/Twitter is to enable him to do so.
The effects of our acts in the world can be completely contrary to our beliefs and intentions. This is is such a case.