Do microniche sites still work?

Hey guys, just have a short question here.

A few years ago I got access to a course and put together a few microniche websites, hoping to make them successful and grow them substantially over a long period of time. Obviously that didn't happen or else I wouldn't be making this post, but my question is about the basic viability of microniche sites right now.

I had two main ones that I was putting time into. One of them was about survival and survivalism, so it had content about how to survive on your own in the wilderness and content about how to be ready for collapse of the government, how to be self-sufficient and live off the grid etc, and I don't really think it was targeted too well to be effective, like I should have stuck to one or the other and gotten more involved, learned more about it and figured out how I could better provide value to customers.

My other website was on aquaponics, so basically how to create a self-sustaining system that grows plants, raises fish and actually gives you food to eat in an environmentally sustainable way. This topic was very interesting to me but I never got much end result from it and eventually gave it up.

My question today is how relevant are microniche sites? Is it worth it to make one and how much success can you actually get with just a little website? What size website should you make that's actually worth your money? I welcome any and all replies.