I have two overarching reasons why Budgie is popular: KDE's rabid craving for new features sometimes comes at the expense of stability, and Gnome's workflow ain't for everybody.
Budgie is simple yet has a moderate amount of customization available. To my eyes it is prettier than Cinnamon. Yes, I can do more tweaking with KDE, but that's a reason I don't want it on my main machine. Sometimes I gotta accomplish stuff.
For Solus, whatever the DE, I like the limited repos because the taste of the developers overlap my own. And the packages are WAY better quality than most. Insync, Bitwig, and Chrome (for work) is there. I only use Flatpak for XMind and Shortwave. Not bad.
I always flirt with KaOS, a KDE-centric distro. It is on a small SSD here. Usually there comes a wake-after-sleep failure or strange artifacts on the screen for no apparent reason. OpenSuse runs well, but there's really no reason to go through all that these days. Ubuntu 23.10 is a very good release of a Gnome desktop. But I tire of working against the workflow. Since I'm in my 60s I figure my own way of doing things is good enough.