This is wrong on multiple levels. Pederasty means attraction to adolescent boys and not prepubescent ones as you seem to imply. Ephebophilia means attraction to adolescents of either sex, whereas Yaoi just means any animated gay porn, even of much older people. And shotà means young boys, from mid-teens down.
You say Shinji and Tai aren't shotà but literally everywhere else calls them shot, it's only this board that does not. Like when rule 34 released restrictions on "shotà and loli" content that included teen boys like shinji. And English speaking boards like 7 chan and 8 chan (rip) shotà boards also had been many threads about teenage shotà. The entire English speaking internet, apart from this one board, calls teen boys shotà. You are wrong.