Personally I think what you wrote here is happening since certain particular genres are reappering every week where as others are basically non existent here.

Even if we assume that whoever liked RTSs left GOG, though, surely the people they left behind don't imagine it's a niche genre taste.

Woolfe: The Red Hood Diaries will be coming to GOG:
http://gamedeveloper.com/view/pressreleases/223067/WOOLFE_ENLISTS_OVER_1000_PLAYERCREATED_TOY_SOLDIERS.php

I love RTS's and have for nearly 20 years, and I'm here proud and strong :)

I also own every single RTS on GOG :)

A Bird Story, the sequel to To the Moon will be on GOG November 5:
http://www.ign.com/articles/2014/08/12/to-the-moon-sequel-a-bird-story-release-date-announced

Has anyone posted Satellite Reign? http://satellitereign.com/

They say it's going to be DRM free and they hope to bring it to gog (as well as the obvious, steam).

Wasn't this game supposed to come to GOG? It's for sale on Desura now. I'd much rather buy it here.

Yes.

Hmm, so where is it? Perhaps still in GOG testing. Or waiting final patching of the mentioned issues.

Well they did say "MIND: Path to Thalamus is priced at 13€ on Steam, available today on PC and eventually on Mac. It will soon be on DRM-free platforms such as GOG and Humble Bundle, thanks to SurpriseAttack." Soon could really be at any time. "Looks at Crawl"

Seems DRM-free on Desura already, so I'm guessing it's either going through the GOG review process, or has already been turned down.

and on Humble: https://www.humblebundle.com/store/p/mind_pathtothalamus_storefront

And with a little discount to boot. Tempting, but I'll still wait on the word from GOG. I do hope it's in their pipeline.

Well most games are released here days or months later then on other platforms so im not surprised at all.