Why does Japan sometimes region lock dub and UI translations via steam?

I know Japan did this for The Last of Us, Days Gone and Helldivers 2 via steam by region locking Japanese translations of those games (both the UI and dubbing) as there is a disclaimer stating that Japanese audio and interface is only available towards Japanese players (as in having a steam account in Japan). I think it has got to do with the overall demographic on Japan having a large player base who demands an official Japanese dub but never released the language pack internationally.