For me it's PeppermintOS.
I started my Linux adventure a few years ago, and haven't owned a Windows PC since.
I currently use Arch on my main rig, and I wanted to install Linux on two old laptops that I found laying around in my house
I then remembered the first distro I ever used, which is PeppermintOS, and I was amazed at the latest updates they released.
They even have a mini ISO now to do a net-install with no bloat, with a Debian or Devuan base.
Sadly, I believe the founder passed away a few years ago, which is why I was really happy to see the continuation of this amazing project.
Doing changes right is a bit hard. With immutable Distros, some changes are easier like adding or removing packages, bur core OS adaptions are harder.
But for example how would you convert regular Ubuntu to
This all gets messy, so people choose small distros
I'm on arch, which I consider one of the larger distros, where most such configuration is very simple. Not sure what rolling mesa is. I probably wouldn't recommend Ubuntu to anyone who is against using Snap, but there are many distros to choose from if you want KDE as well? It's more a question of why people would go for Hannah Montana Linux (figuratively speaking, some very niche distro).
But to respond to your core point, sure. If you do have a lot of customization needs for whatever reason, then by all means. (I still don't get it)
I meant that its not easy to customize deep system changes and keep them working well, on your own.
There are Forks of Ubuntu like TuxedoOS, PopOS (?) and more that do rather big changes that could break things. So its best to have a community support them.
But I agree on your point. Currently I am on Fedora Kinoite but still dont switch to ublue, as I can do the changes on my own, on the official base.
If I had an NVIDIA card though, I think ublue is the only Distro thats reliable enough (if an update would break, you simply dont get it)