The preview video looks nice. It would be really cool if the dev can consider support Linux in the future, even not in the first release.

This doesn't really guarantee anything for the final product, but this game has a "free demo/prototype" that has a Linux version:

https://vfqd.itch.io/terra-nil

I've been told that it wasn't an option for the demo but is planned for the full release.

Update from March 22:

"Linux & Mac release info

Regrettably, after doing more testing on our Linux and Mac versions, we aren't satisfied with their performance and we want to optimize both versions before releasing them. The PC version is still on schedule for March 28.
We're really sorry for any inconvenience caused, but we want folks to have a good experience when you get to play it. We'll provide an update about Mac and Linux as soon as we feel they're ready!"

Source: https://store.steampowered.com/news/app/1593030/view/3728456836549344064

I don’t know for how long it has been, but this game does have a Linux version. It’s just not on GOG for some obscure reason, only Steam.

I'll get more info !

It seems the Linux version is now on GOG!

I don't know when it happened...