There is Dahlia OS which looks fairly promising but development takes time and it is only a small amount of people.
I like the idea of the OS being more embedded focused like Android and Chrome OS but I don’t want Chrome or Google.
Is there anything else I should look at?
Cloud native just means that it uses tools like distrobox. I have used both and ublue has way better defaults: preinstalled drivers, codecs, update tool. Aurora and Bluefin are very similar, one kde one gnome, but bazzite is pretty different, it comes with a bunch of gaming features and tools and waydroid