Dear Ladies and Gentlemen of the GoG community,
I would also like to re-emphasize that question:
The 3 year old System Shock Demo for the remastered version in my GoG store is offering a Linux client.
It works very well, and from time to time I still play it, although it is just a demo. The Unity engine works well, at least on Windows and Linux.
Now seeing the release of the remastered version being on the verge of release, but only listed available for Windows makes me a little bit sad and wonder:
1) Maybe the developers had to cut short on this part, in that case we can't blame anyone here on GoG.
2) The Steam and Epic games store also only offer a Windows version.
Their homepage shows pictures of Xbox, PlayStation, Windows, iOS and Linux, but the FAQ does not offer any information about that. Therefore, I think that Windows as a platform for the game is the current reality, with others being maybe possible.
If this game comes out for Linux, there definite will be multiple purchases - not just for me but also as gifts ;)
I will check the status/progress in autumn again - have a good time!
Yours best, as always,
M