My stance is this:
- Short hair should be gender neutral.
- I don't think we should have short-haired male or short-haired female tags. I don't think something as common as hair length deserves to be gendered.
- We should be very conservative about when we gender tags.
- When we do gender tags, we should normally keep the male and female versions separate.
I'm not convinced by the "if we tag short hair on guys then I won't be able to find short-haired girls" argument. Literally 25% of the site is short-haired girls. You can't tell me something is too hard to find when it makes up a quarter of the site.
If anything, I think short hair is already flooded. Hair length tagging is highly variable, and short hair is already filled with things I wouldn't call short hair (not to say they're wrongly tagged, but they're not what I'm hoping to find if I'm looking for short-haired girls).
I don't like the idea of a short-haired male tag because hair length is an extremely common thing and allowing it to be gendered it opens the floodgates for everything else to be gendered. If you think color tags are bad, just wait until we get *_(male) and *_(female) versions of everything. This is exactly what happened with color tags. Taggers saw that we had color tags for some things, so they took it as a license to make color tags for literally everything, and by the time we started trying to crack down on it, it was too late.
On the last point, when we do have male and female versions of a tag, I think it's usually best to keep them completely separate. I think it was a mistake to do things like make male pubic hair a subset of pubic hair, or dark skinned male a subset of dark skin. This often creates more problems than it solves. It's like saying that yaoi and yuri are the same thing and should be under the same umbrella tag. Technically that might be true, but nobody actually wants that.