Any setting where I can filter explicit games? I don't want to receive their recommendations and discount offers on them.

If that existed, we wouldn't have to get a "censored" version of Huniepop 2.

Why GOG doesn't bother to install the red bead door on the website in some manner is a completely baffling thing they've never explained.

There are no "explicit" (sexually, I presume) games here. All of the games who actually have explicit versions (Starnova, HuniePop) need a patch to de-censor them if you buy them here and want to play the "full" version.