I'm an oldfag so I remember Heero/Duo being a big thing in the early to mid 00's. Gravitation wasn't that big in the circles I hung around with, I think it was deemed a bit cringey even at that point. Inuyasha/Sesshoumaru was popular too when the anime came out, Loveless was huge
in 2005 and outside of anime Harry/Draco from Harry Potter was everywhere. And of course Naruto/Sasuke was popular ever since the anime first aired, not much has changed with that one.
The 00's fujo circles were quite different from nowadays, people didn't really give a shit if the ship was incest/abusive
/whatever or not if the two guys had good chemistry and looked hot together. Now you got this whole fucking kangaroo court of twitter zoomers demanding human rights for cartoon characters.