The BSDs have that philosophy AFAIK.
Yes, the OS is separate from the rest and the experience much more streamlined than Linux... but it doesn’t support WiFi beyond 802.11n which is too slow for me. If BSD supported modern WiFi I’d have switched to it on my daily laptop long ago!
(yes I know there are ways to use another package manager on a given Linux distro, even homebrew, but I'd rather see a strong distro built around that idea, not even trying to provide every-friggin'-thing in the distro's software repos)