Sry but I’m an Exotic along with so many other fandoms. And I think that sometimes they sing bad live or acapella. But they sing good also. If they didn’t sing good would they even be casted into SM? Not everyone of Exotics thinks the way you say. Don’t put everyone on the line because some say a thing or two.
An example: Kwanghee from ZE:A doesn’t really sing that good either, but I love him anyway because of if personality. And I don’t like Kai in EXO because he sings good (and btw… I dunno if he sings good… Just heard him rap). I like him because he is good at dancing.
Another thing… It’s wrong that Exotics compare EXO with the other “older” groups as TVXQ and Big Bang (example here again ^^). Because EXO debuted 2 years ago (ca) and TVXQ have had some time to develop more so Yes it is obvious that they are “better” and have more experience. But you learn with practice and above all - You learn from your mistakes.
But just because Exotics act in an inappropriate way, it doesn’t mean that EXO are at fault. Even they have asked their fans to calm down a few KG.
(I hope you understand everyting… English is not my native language ^^ Have a nice day! … Or night… depends on where in da world you r :) )