HumanamuH is not meant to be a dating site in particular. But I assume wherever people meet, some of them will want to date. I like the idea of HumanamuH bringing love to the world, so I'm fine with it.
The possibility to state one's orientation and whether one is looking for a partner is there for at least two reasons.
If you don't want to date, you can make that clear upfront. Hopefully this will reduce unwanted requests.
If you want to date, it's easier for everyone involved if the orientation is known beforehand.