Trademarks can be held by an organization, not just by one person. This is how Apache software works, for example. In that case, there are bylaws in place to ensure that the interests of different people are represented, decisions can be made fairly, and toxic people can be prevented from killing the project.

In contrast, projects such as Python have a "benevolent dictator" moderl where one person has the final say about the direction of development. There is nothing unethical about a BDFL model in open source; it's just a choice that a community can make.

You seem to be deliberately confusing yourself about the distinction between forking, which is always allowed, and representing your fork as the original project, which is never allowed. If you are still confused, think about it this way: would you want someone to attach a bunch of malware to your project and redistribute it under its original name, as if it were your version? You can't prevent this without trademark law.