Turok 2 and Dying Light still do not have their Mac and Linux versions available here on Gog.

What is going on?

No not really there are still some indie PC versions of video games released for sale for Linux and for Mac.

The Linux video games marketshare and the Mac video games marketshare are a whole lot smaller than the Windows video games marketshare, so most AAA video game publishing companies and AAA video game development companies will not release the PC versions of their video games for sale for Linux and for Mac.

But the sad thing is that many times when there is a Linux or McIntosh version elsewhere, they do not come to GOG.com.

Pretty much this along.
CDProjekt/GOG doesn't have the staff/money to really get deep into Linux + Linux gaming/gaming support without going deep into the red.

GOG could opensource the Galaxy client source code and have a community created multiple platform Galaxy client within a few months, but that would require major work. AKA windows software API calls require different solutions in Linux unless a version of WiNE is included with every client/game...which is pretty much what Steams Proton is.

So, the actual answer is, aside from Galaxy (which does have Mac support), none of this has anything to do with GOG. It's up to the publishers. For example, Feral Interactive insists on DRM for Mac and Linux, which means Steam-only. Hence only Windows versions of Bioshock and XCom here. Apparently the Mac and Linux ports of Age of Wonders 3 were done by a third party who doesn't want them on GOG for whatever reason. Turok 2 is a weird case, since that publisher does consistently have Mac/Linux versions here; don't know what's going on with that. But it's not up to GOG. (I'd buy it if it eventually gets here though.)

To this day I'm still waiting for the Linux version of Turok 2.
Dying Light has Multiplayer, and as we know there's no Galaxy for Linux which may be the (lame) reason why.

I have honestly gave up on Dying Light, I got it on a sale a few months ago and it works very well in Wine + DXVK.

@eric5h5: The devs of Age of Wonders 3 didn't want to manage 6 builds and without Galaxy they saw it a hassle. They said that at a time when Galaxy wasn't released, what's worse is that even with Galaxy for Mac, they didn't even bother, yet they were quick to advertise their new game here.

Nah, they haven't abandoned them. It's just a similar story to updates; you never know if each and every game will actually get them.

feral interactive normally handle them ports. iirc, feral don't support drm-free. i don't know who owns the rights to the mac/linux variants but this is my theory atleast.

So Gog Galaxy is a problem for games which need it for multiplayer?

Turok 2 does not need Gog Galaxy for multiplayer.