The Epic First Run programme allows developers of any size to claim 100% of revenue if they agree to make their game exclusive on the Epic Games Store for six months.
After the six months are up, the game will revert to the standard Epic Games Store revenue split of 88% for the developer and 12% for Epic Games.
I don’t think GOG is going anywhere, perhaps the poster above you just used weird phrasing (English might not be their first language)
I should’ve just added “Never forget [buying games from] GOG!” already 😅