Tarhiel: I, for one, would be glad if they would post a news post about this, I also would not know audit this unless some other user mentioned it in other thread which I was reading at the time.
Definitely wouldn´t hurt to be more transparent about this. Not all of us go to forum everyday, and this removal is quite on a short notice.
Spectrum_Legacy: For me it was similar - my friend on steam told me about it after he read it somewhere (I dunno where, he doesn't use gog at all, despite I keep telling him about good deals and giveaways here). He just mentioned it to me because as he knows I like my old games and use gog... A bit ironic in a way that I as a gog-er haven't seen it myself, though in all honesty I rarely check other than game-specific subforums as general one is chock full of some forum roleplays and pretend games and theorycrafting stuff I can't relate too well with, nor care much about.
Stickying the post made it more visible to those who use general tab at least which is a lot better than nothing, though there's room for improvement like said email/newsletter mention (gog is pushing them out during sales and getting more users subbed via giveaways anyway), mention on the front page/news section, etc.
Maybe any mention of delisting on a platform is seen as a bad look by marketing or pr department, so they don't advertise any game's impending digital doom. I would understand that, but I'm sure that users are not only interested in arrivals here, but also departures, no matter how much it sucks to see.
Couldn´t have said it better myself.