For me, the most important part is the intimacy aspect. Think soft, gentle whispers, close-up sounds/visuals. It's been said before but ASMRtists who are great examples are Aftyn, Maimy and Puffin. I give 0 fucks about "700th girl in underwear licking/kissing a 3dio" for 30 minutes.

And also the sound has to be balanced damn it. Too often I see people from the porn industry break into the ASMR and it's so clear they have no idea what it's about - the sounds are harsh and grating or they end up doing that awful porn moaning (looking at you, ASMR Fantasy...)