the mangakas started it by making an established stereotype of seme and uke, thus the birth of it's term (and all of it's other classifications... if you want me to elaborate more about the terms and classifications the japanese mangakas and fujoshis developed, i will). it can't be helped because BL is made by women so they somewhat project the position thing in their writings. and the people are just following through. however, i guess a few will be bothered by it. i'm always in for non-stereotypical couple tho and i don't see anything bad with what people call them but that's just me.
╮( ̄▽ ̄)╭ can't exactly call yaoi (in particular) a work of art though. but there are exceptional BL mangas that are worth calling that but they are few and far inbetween yaoi porn.
yes, I know which is why I don't like the term fujoshi either lol even though i love BL and yaoi... i don't mind learning all the terms, am always curious...i already know about 'tachi' and 'neko' and also 'pitcher' and 'catcher' but that's about it.
About yaoi being a work of art... i guess it's the French in me (i live in a french-speaking country)... For the french, comics/manga/bande dessinee has been considered legitimate art since the 60s and is called the ninth art, after architecture, painting, sculpture, music, poetry, dance, cinema and television. Erotica or porn does not matter, it is still called the 9th art and i like that...although i agree with you, some drawings from old manga are not as pretty lol...but beauty is in the eye of the beholder as they say :)
Most yaoi has zero realism. It's why gay men don't like reading it, because they know how wrong it is. Actual gay men aren't strictly divided into ukes or semes, most gay guys are actually versatile. And you can't tell based on appearance if someone likes to bottom or top. And don't even get me started on the insane amount of rape in yaoi.
But try explaining that to fujoshis.

It kinda annoys me when people say 'seme looking ukes'. Just because the stereotypical seme is taller and more masculine than the uke doesn't mean that has to be the case for ever yaoi. It also really bothers me when people address the characters by their position in bed rather than their name. ( ̄へ ̄)