> Why should we believe that these people won’t simply capture more power with more powerful technology?

This is exactly what I suspect will happen. Large companies have consistently and repeatedly destroyed good faith by their behavior and I don't see that changing any time soon. I'm very pessimistic.

Tech-savvy users can host their own infrastructure, install ad blockers, refuse to use social media, fund open source projects, etc, but what about the rest of the people in the world?