yeah it's close, but no dev is currently working on it, atm the main thing blocking it is a big blob of assembler remaining in the rendering code, replacing the CPU rendering code with GPU rendering would be ideal for a native port, but yeah maybe if some interested dev joins, otherwise could be close for a while

There has been a improvements to move away from proprietary file formats and Windows only code, but there's still work that need to be done.

I personally play it using just a default Wine installation on Ubuntu and it runs great.