Again, I’m merely saying what kind of UX Steam has in place that could be used for the purpose. In the terms of a few rather obvious facts that seem to be phrased as a counterargument (?!), it’s another disk (or ten) magically appearing out of thin air.
GOG occasionally makes multilingual releases out of monolingual games. But most of the time (like in the Legend of Kyrandia I just bought) they simply offer you the choice of which to download.
In GOG Galaxy you’re presented with a choice of language on first download. Then if you later switch the language, it often downloads just the language data. Age is not an issue, switching to French or German in the Legend of Kyrandia is a ~3.2 MB download as opposed to the full 84 MB. Which is exactly how I said it could and does work on Steam if someone bothers to implement it for the game in question.
Moreover, I said that there’s a lazier alternative that requires less effort: same UX, but simply download the full 84 MB (or in the case of CMI, the full 1+GB).
The main difference is that GOG cares, while Steam is more of a hard to use dumping ground. Although sometimes I find the dumping ground preferable because GOG might do something stupid like removing the DOS executable from a ScummVM game so you can’t play it on a real device or in an emulator like DOSBox should you wish to do so. I wish they never went through the effort of removing stuff that’s just sitting there not hurting anyone.
I guess I misunderstood what you were saying. This is a very different claim than that there would’ve been a new rerelease in the past ~16 years otherwise.[1] Past experience on GOG shows that new languages often have a way of showing up later, whether for reasons of technical difficulty, rights or difficulty of procurement.
tl;dr I agree with that.
[1] Assuming the German 2002 THQ LucasArts Adventure Pack was the last rerelease. Judging by this review it might’ve still been readily available in '09.
PS It looks like the last rerelease in the Netherlands might’ve been in '04.)