They look sexy because they are  This is something that these people can't seem to get through their fat heads. I don't view a fit model as sexy because "the white cis patriarchy" or whatever tells me I should or shouldn't, I see a fit model as sexy because a primitive part of my brain recognizes an ideal mate that will bear healthy children and be able to protect and provide for them. All of the kinky layers on top of that is just personal preference based on imagination or previous experiences. But at the core of it is basic instinct. When that primitive part of my brain sees a half-naked shamu in a "sexy" pose, it sees an unhealthy, unfit specimen incapable of bearing, raising, and protecting healthy offspring. It will never matter what they say, normal humans will never view them as sexy. End of story.