There's a problem with MacOS because Apple stopped using OpenGL and is forcing their own Metal api which is used only on their platform. That makes porting Windows->Mac games process very difficult and mostly too much time consuming.
Not true. All of the current intel based Mac's support OpenGL out of the box (source
Apple).
Apple's own Metal API is an alternative, not a replacement, and is likely to remain so for the foreseeable future. That doesn't mean there aren't issues: Apple is keeping MacOS on OpenGL 4.1, rather than pushing 4.6. For some games this is a big issue (e.g. Elite Dangerous: Horizons). However, given that Divinity: Original Sin EE worked beautifully on MacOS and D:OS2 is graphically very similar, it's hard to see why OpenGL 4.1 wouldn't be sufficient. D:OS2 is based on a modified D:OS EE engine after all.
I suspect that the main reason Larian are being quiet re MacOS and Linux versions is that they are still fixing bugs for D:OS2 PC. But we'll see.
+1 for Mac (and Linux) anyway.
