I don't know why your dragging centralization/decentralization, business model, Fairphone, etc. into the conversation now. It sort of feels like you're overthinking this.

I often talk to people about Signal irl, most download the app but some folks do. Some people actually want a For You feed and will bounce off Loops, Mastodon, or whatever. That's all fine. These spaces can have content about cars or guns or whatever else without eating the entire world.

You said:

> I want loops/mastodon to be a diverse place that has content from all over the internet.

Again, I think lots of people who are already in the Fediverse want that. But, if everybody who likes cars decides they won't join in until somebody who shares content about cars does, that car community may never show up.

You seem to have interests that you feel are undeserved. Just... regularly share things about what you think is cool. Just do it for funsies.

If you really feel strongly about wanting to make a diverse space, cross promote your stuff in spaces with other people who have the same interests. Share a post, share a video, ask them to follow you. Maybe even start an instance dedicated to the topic if that's your vision.