Do you have machines which "just work"? Not a daily driver machine or server that you mess with every week, but something you set up long time ago and that has been working even since. Something that you may only log in few timers per year, if that.
I stopped using Gentoo when I got my made my first "production" system: I made it, people started using it, and it was "done" - as in, there were no more any reasons to log into it daily, or even weekly. I'd still want my security updates and very very rarely there would be a new feature that required new package, but otherwise I wanted system to be steady. And Gentoo is a horrible fit for this usecase - even on my personal desktop where I updated weekly I had emerge build failures practically every time; and a system which might not be updated for months would be even worse. So I went to Debian, and it was good (especially with unattended upgrades), and I eventually switched all my machines to it.
If you use Gentoo, do you have any machines that you don't tinker with weekly? How often do you update them, and how often do you need manual intervention to finish the update?
Oddly enough, on my family's farm, we got a DeLaval voluntary milking system, i.e. milking robot. Very pricey piece of gear. And several of it's embedded computers for some reason run Gentoo.
Well, here is your answer why so few people use gentoo.
I can count at least 6 linux computers in my household (this includes stuff like work laptop(s), fileserver, my family member's PCs, and that raspberry pi which only acts as a camera server for my 3D printer). And the life is just easier if all of them run the same, or at least very similar, systems.
I stopped using Gentoo when I got my made my first "production" system: I made it, people started using it, and it was "done" - as in, there were no more any reasons to log into it daily, or even weekly. I'd still want my security updates and very very rarely there would be a new feature that required new package, but otherwise I wanted system to be steady. And Gentoo is a horrible fit for this usecase - even on my personal desktop where I updated weekly I had emerge build failures practically every time; and a system which might not be updated for months would be even worse. So I went to Debian, and it was good (especially with unattended upgrades), and I eventually switched all my machines to it.
If you use Gentoo, do you have any machines that you don't tinker with weekly? How often do you update them, and how often do you need manual intervention to finish the update?