Kids are actually fairly big into indie horror, judging by my son and his friends, and these are somewhat like old school adventure games. My son has even brought up SCP, despite only being ten years old.
Stuff like Hello Neighbor, Poppy Playtime, Bendy and the Ink Machine, and of course the juggernaut that is Five Nights at Freddy's have gotten quite popular. Not as popular as Fortnite, obviously, but it's more than a tiny niche.
And the latest FNaF game, Security Breach, is pretty much a full fledged adventure/puzzle game that happens to have some jumpscares and a scary premise.
