KaOS

KaOS takes an unusually narrow, opinionated approach for a general-purpose distribution: it only ships KDE Plasma, deliberately favors Qt-based applications over GTK ones where a choice exists, and builds its packages independently rather than basing itself on Arch, Debian, or any other distribution (despite using pacman as its package manager, adopted for its technical merits rather than any Arch lineage). That narrow focus lets its small team polish the Plasma experience more tightly than a distribution trying to support many desktops equally well, at the cost of being a poor fit for anyone who wants GNOME or Xfce instead. It's a favorite among KDE enthusiasts specifically for how closely and quickly it tracks new Plasma releases.