I do think more body types should be represented, not just heavier people, but thin, tall, short, whatever. Variety in personal style, too, we should have characters representing different cultures and trends in their dress/hair/body mods. Just.... variety. I don't think there is any ill intent or anything. Artists tend to end up with a few body templates that they recycle, because they are on a deadline and it's just what comes out, most comic art also tends to be stylized, which leads to more exaggerated body types. But I think there should be more effort to represent a variety of body types. And to be fair, there have been moves in that direction, with like, Squirrel Girl being depicted a lot more curvy, they brought back Big Bertha (I know, the book failed, but they tried), and a few others like (ignoring just Marvel for a moment since this one is a fairly important one) the Faith books. However, superhero comics do, like action movies and similar do, have a built in excuse *to an extent* since the characters lead extremely active, athletic lives, and it will lead to the characters being naturally more fit. But, i mean, it's not like there is only one 'athletic' body type, either:
*edited to add - also, as sometimes happens when this type of discussion comes up, I think we need to not paint people who are thin/fit and being an "unrealistic" body type. I am 105 lbs, give or take a couple pounds, have been since high school, it's just in my genes, same as being on the heavy side is in some other people's genes. I take after my dad, and his side of the family, with a couple exceptions, tends to be very thin and able to lose weight more easily than most. Genetics, that's all it is. And from my perspective, when this topic of discussion comes up, people often over react, and say that people like me, or people who go to the gym and get ripped just cus they want to for whatever reason, should be hidden, that we are not "realistic" ideals, because some people really would have no hope of achieving that body type without doing something dangerously unhealthy. (and yes, I do realize that some models in particular do starve themselves, and I am not saying that sort of thing should be encouraged) But being 105 lbs is perfectly realistic *for me*, I am healthy at that weight and it is what my body just naturally tends towards, and I should not be made to feel guilty for what I look like any more than a heavier person should.