Cosplay elitism will almost never fade, and it will always be a little ingrained in our psyches. As Sunara mentioned, when given the same cosplay, same quality, people will naturally gravitate towards the person will the more "accurate" physique. This does not mean that the person with the "less accurate" physique shouldn't try, they just have to work a little harder to make their cosplay shine.
Personally, I am a large person, I'd look perfect as Chouji or the Heavy from TF2, but I'd be ill-suited to the more standard of gaming and anime fare. And, again, personally, I'm OK with that. I'd rather cosplay a character that I loosely resemble than try to don some lighter character's wardrobe and pretend I'm them for a weekend. But that's me. I have no problems with people cosplaying characters that they don't perfectly match. Do what brings you the most enjoyment.
Personally, I am a large person, I'd look perfect as Chouji or the Heavy from TF2, but I'd be ill-suited to the more standard of gaming and anime fare. And, again, personally, I'm OK with that. I'd rather cosplay a character that I loosely resemble than try to don some lighter character's wardrobe and pretend I'm them for a weekend. But that's me. I have no problems with people cosplaying characters that they don't perfectly match. Do what brings you the most enjoyment.