I like how simple it is. It’s made distrohopping very, very simple for me over the years. The only pet machines I have are my actual dev boxes. The rest are cattle I manage with other tools. Galaxy has also made it much simpler to consume other Ansible which used to be really annoying.
I’m on the fence about Nix. When I first saw years ago it was yet another package management system. I’ve seen enough interesting things with it now that I’ll probably try it out the next time I want to rebuild my configs from scratch.