It's been released on Steam. Hopefully, it get's on Gog also. :-)
Checked itch also, but there seems to be only the demo so far.

@GOG: Any news for us?

I sense something good heading our way ;)

Please mind that I'm not downvoting you, but GOG is my store of choice and while I have some DRM-free games on Humble and Itch.io I'd rather have a GOG version, keep my main collection here, and possibly and cloud-save and achievements!

Same here.

I have no desire to "shop" other stores (such as Itch.io or Humble, etc.). I like having one main collection in one place. That, for me, is GOG.

This game appears to be getting mostly decent reviews on steam, so I'd look forward to checking it out here.

And you are right! GOG agree to have the game on the store!!!! My firend ask to Rotorist through Diacord and send me the screen capture :O

itch has had a launcher for some years now. No clue if it's up to snuff, but it's there, and it's open-source and supports Win + Mac + Linux, to boot.
There are also forums, as well as the ability to post and reply to comments on product pages (if the developer has enabled that feature).
No idea about the regional pricing or support for currencies and payment methods in regions outside the U.S.

You can more or less guarantee it will be rejected if it has anything in it that might upset the chinese Govt.