I am expecting a lot of Disco Elysium, here...and nothing wrong with that!
A video gaming student organization I was once part of actually had a vote on their favorite sayings. The winner was the evergreen "Perhaps the same said could be said of all religions..." from Castlevania: Symphony of the Night! https://www.youtube.com/watch?v=OMTizJemHO8
My personal favorite? It's hard to say...but hey, that's what the scientist in Half-Life can comment, word to word! So maybe I'll put forward, said by the aforementioned: "My god, what are doing!?"
"In time you will learn the tragic extent of my failings." Or just Darkest Dungeon quotes in general really.
Also a lot of SHODAN quotes burned into my head. "You move like an insect. You think like an insect. You are an insect. There is another who can serve my purpose. Take care not to fall too far out of my favor. Patience is not characteristic of a goddess."