Unpopular opinion: non-pro can handle the OS just fine and then some. Try out SailfishOS (unfortunately not OSS) - it’s as smooth as butter. Or UBPorts - it works great (unfortunately both Sailfish and UBPorts aren’t as polished when it comes to actual hardware support on PinePhone, but they show nicely what could be done). I don’t think I even need to mention Sxmo, which is no surprise that it works great, but its approach is definitely not for everyone.
It’s just Gnome/Plasma that are mainly developed for “big” computers and are pretty wasteful. But the situation is definitely improving.