What do you mean with “PC”? Is a smartphone a PC? Is a steamdeck a PC? The Laptop of a government employee? A Raspberry Pi? What about a TV-box or an e-reader?
Because if you mean in general on non-server hardware it’s probably some weird Chinese/indian fork for their government PCs.
Otherwise it could be Arch due to the steam decks, but then again it depends on how tightly you define “distribution”. As others have mentioned, is Xubuntu their own distribution or does it count as Ubuntu? What is Mint/Pop!_OS?