Sure, people are trying to start them up.
You know what they face? Collusion from Big Tech:
1. Apps that directly access the website get banned from the App Stores;
2. Even general purpose browsers - ones for protocols NOT based on HTTP - get banned from stores if they DO NOT ACTIVELY BLOCK these right-wing alternative domains;
3. Web hosting companies reject them, or throw them off after initially accepting them because the host company gets threatened;
4. Payment processing companies refuse to do business with them;
5. They get vilified in the press because bad people post dumb things - and then if illegal, get banned afterwards...
...meanwhile bad people post dumb things on the mainstream platforms, and if liberal, never get banned;
Etc., etc.
Check out the history of Gab, Bitchute, Parler, Minds, etc. to see what goes on.
The word is:Collusion.
This is exactly the case.
There are alternatives but the big players collude to block them.