Gersen: The issue with Absolver is that it's basically a PvP multi-player oriented game with a small SP campaign.
So the issue is really that it is an MP game with an alibi SP part (aka tutorial).
Well, tough call. Ideally the MP part would require no client - problem solved, but sadly that's not fashionable anymore...
MP only games with a client requirement can't be called DRM-free in any meaningful sense. So "the SP"... 30€ for a tutorial, that's all what pure offline players get. The rest is "leveling up for MP" as you wrote, and thus tied to playing online.
The game doesn't really "fit" here, I guess. On the other hand, it's perhaps a good game (for MP) and some people are probably glad they can get it here instead of The Other Place...
I guess one problem is that in more and more games the borders between online and offline get blurry, like Dying Light, Dark Souls, No Man's Sky... and the online parts will always require a client because that's just how it is. And GOG has to make a decision on how to handle games like that.
Stripping them of their online components just for the sake of "100% DRM-free" feels silly, because nobody gains anything, and the people interested in MP stuff lose out and buy Over There instead. Not releasing them at all means there's no DRM-free version available at all. Releasing them as they are angers the DRM-free fanatics. And convincing the devs to not make games like that? Good luck with that.
samuraigaiden: I'll say one thing. If a random user starts using my forums or my social media posts comment section to call for a boycott of my company or my products, I would ban that user in a hear beat. Clearly GOG is a lot more tolerant.
^This.