I just found an obscure Linux distro that's outstanding on old hardware
Vinari OS 5.0.0 KRYPTON is a Debian 13–based GNOME distribution providing a curated, ready-to-use desktop with Flatpak/AppImage support for new and experienced users.
I found the new Asmi Linux fast and fun to use - if you're not afraid of a little setup work
Asmi Linux releases updated Ubuntu 25.10 and Debian 13 editions with customizable desktop layouts, a redesigned CSD interface, and optional paid Ultimate software bundle.