I use AsteroidOS since afaik it's the only working FOSS watch OS. It's still pretty bare feature-wise. Everything has to be done via PC terminal, even loading custom background images. There are basically no apps published by the community.

BUT now I have a watch on my wrist instead of in a drawer, it interfaces with my LineageOS phone, and it's not uploading all the details of my boring life to Google :]

I need to learn how to fuckin code...