If you think something like post #5576530 or post #5576879 looks remotely masculine you've drank way too much kool-aid. The only reason these posts are tagged 1boy is because it's canonical knowledge (which doesn't even necessarily apply anymore). This is pretty contrary to how we generally prefer to operate the site. If I'm browsing for females as someone with no knowledge of GG or its characters, I would expect to see those two images, and if I don't then clearly we've gone wrong somewhere.
Obviously this only applies in cases where the character in question is indistinguishable from female (or male, I suppose). post #5573960 doesn't really look like a girl (because of pecs), even as a futanari enjoyer. Yes, that means in some cases one character would have to receive different gender tags between two posts. I don't see why this is a huge problem. We aren't going to insist on tagging a character with blue hair when their hair is drawn purple just because they normally have blue hair. If we really wanted to we could tag them with both 1girl and otoko no ko, so people who absolutely hate the idea of seeing "males" (even if they'd have no way to tell) can still blacklist them.
As for transgender, I think the tag is fairly poorly named for what it is intended to be used for. If people see a tag named transgender they are going to apply it to transgender characters without really caring what it's intended to be used for. Remember, the average Danbooru user isn't reading any wiki pages. I would be fine with renaming it to something more descriptive and repurposing the transgender tag to be used as a canonical tag. We already canon tag otoko no ko and virtual youtuber (among others), so one more won't be the end of Danbooru. It'll have to be pretty strictly only for canonically trans characters though, so we don't end up with it being flooded with irrelevant content like random pictures of femboys.
tl;dr we should really just be doing TWYS. Not tagging completely female-looking characters as female just because some people get their rocks off to the knowledge there might be a dick is kinda ridiculous.
Tamarinne said:
If the issue is solely about visual tags at all, why bother using genders at all? Why not just stick to tagging the number of penises or vaginas in an image?
Three-quarters of this site is SFW. If we're only tagging pussies and penises then you will not be able to search for a huge amount of content on this site. This might not matter to the average coomer but it's a pretty horrible idea.