I would wager a guess that it’s your regular interests. YouTube sees that people who like machining, blacksmithing, etc. have a good chance of also being conservative. You probably are just part of the odd cases where you like those hobbies but aren’t conservative.
Your post raises an interesting point, though: even if YouTube didn’t intend for their algorithm to be a pipeline for radicalism, simply by encouraging engagement and viewership, their algorithm ends up becoming a radicalization pipeline anyways.
It’s really fine if nobody shows up. If anything, you could always just post or cross post something every once in a while to help the community pick up steam. What you should be concerned about is too many people showing up. The reddit admins (as well as certain sections of redditors, it seems) have forgotten that moderating is pretty tedious and not everyone has the time or energy to spend on moderating. If I were you, make your moderating policy clear from the start and stick to it as objectively as possible. When changes to that policy has to be made, clearly communicate to your community what changes are made and why. Some changes will not be accepted by the community, and you should do your best to remind yourself that it’s not a personal attack on your values if they disagree.