Good to know, still the obscureness of this function or semantics led WSL1 to be incompatible for a long time (Also skimming this article touches upon some 0-sized mappings being an issue?).

Regardless this led WSL1 to have fatal incompatibilities for a long time, iirc basic stuff like the rpm system or something similarly fundamental for some distros/languages relied on it. And once WSL2 existed people just seems to have gone over.