This has been brought up several times in the past, with people making solid arguments for why it should be removed, but I still see it happening. So, why not try again to bring it up? If it's a dead horse, it's overdue for a beating.
A reasonable user would expect implications to be always true. For example, 2girls implies multiple_girls, but wouldn't implicate couple, because the image in question may not depict a couple, it just happens to have two women in it. So, why do the cosplay tags have an auto-implication? If that character is not depicted, then they are not depicted, plain and simple.
In general, "tag what you see, or who made it, or with what they made it, or where it came from" is a good rule of thumb for useful tags (and is also common sense.) So if you want to see pictures of a character, and you search for them, the results might include pictures of completely different characters just wearing your desired character's clothes; you're not getting what you asked for, you're getting unnecessary extra stuff. If there were no auto-implication, no one would manually tag the image with the cosplayed character, not if they were following "tag what you see, etc." (To contrast, consider the "meme" tags, like crying_aqua_(meme), which don't get the auto-implication treatment. They do not suffer from this problem.)
Furthermore, it makes searching specifically for pictures where both the original character and someone else cosplaying as the character are depicted. See the excellent arguments laid out here: forum #152245 and forum #152248
Implications exist to save us time without mucking up search results. This implication mucks up the search results and makes some searches impossible. Ergo, it should be removed. The fact that it creates objectively wrong tag mappings is just icing on the cake.
I don't know how to formally petition this. If someone knows the syntax for requesting an unimply with wildcards, please let me know and I'll be glad to do it.
