NaN Industry VR will turn into a free and open-source game during the month of November.
You live and learn! The general administrative overhead of managing a small paid game doesn't justify itself at all. This game didn't sell well enough to even cover the $100 price you need to pay to Steam to put your game up in the first place. What I learned in this experience is that it doesn't really make sense to put non-professional games on Steam---or at least non-professional VR games, whose market fraction is still quite limited.
What prompted this? I've recently put two games (including NaN Industry VR) on the unofficial store "SideQuest" for the Oculus Quest, and this game already has many hundred downloads there. The key difference is probably that it's free. People expect less from a free game and are more forgiving of, say, the amateur look; but more people play it and can really judge from first-hand experience. And let's be honest, people playing the game is really the main thing I expected from this whole adventure of publishing a game.
Oh, and BTW the open source Quest version is at https://bitbucket.org/arigo/nan-industry-vr/ . It already contains more features than the PC version (like a tutorial), prompted by discussions with players. I will update this repository with a branch for the very similar PC version.
Thanks everybody!