I actually went to look into the examples mentioned above.

Hitman was apparently playable with “some targets” and other stuff locked behind online functionality but the base game was playable without. So this part definitely feeds into the “screwing people in new and exciting ways” that you mentioned.

For Deus Ex MD - apparently the binaries themselves were actually the DRM free ones, but the package that they gave GoG basically redirected all the DRM calls to Steam, which… resulted in a weird situation where it’s half stripped of some DRM measures while the other half required an actual crack to kill those calls that were redirected to a different platform entirely… so overall I wanna chuck it to a lazy “let’s get some brownie points and release it on GoG but let’s use this intern to package and ship it cuz we can’t be arsed to do a proper release” type of scenario.

Do I blame GoG for not checking it throughly? Yeah, a bit, but at the same time the onus should be on the providing party to deliver an adequate product that’s up to the requirements of the platform and if it’s not, maybe have a financial penalty clause for non-adherence in the distribution contract or something, I don’t know, I’m not a lawyer or anything.