Lizzo and anyone of similar weight manage to offend people just by existing in their bodies. I am personally a fan of body neutrality. We all for better or for worse lol possess a corporeal form, we have a body that is of use to us to different extents (there are also disabilities that render our bodies more or less "functional"). We will all someday also die and our bodies will either be cremated or we will rot, be consumed by other forms. While we are still alive however we do not see our bodies as vessels that we are to take care of in a way we see fit to serve us as we see fit, we unfortunately exist in complex ways and are socialized to hate our bodies, to scrutinize ourselves, to strive towards this or that trend so plastic surgeons and beauty industry can profit off our insecurities. someone else's individual health is also really none of my business (and i am more concerned with structural issues surrounding accessing health services) and people do not have to be healthy to deserve to be seen, heard and photographed. and yes, we should address how poverty influences eating habits, how people are sold junk but that is a bigger more nuanced issue. Many people who are thin or within a normal BMI could be described as having disordered or nutritional enough eating habits. Many people we see on covers of magazines live "unhealthy" lives in other ways. Moreover we cannot really tell all that much on the state of someone's health just superficially looking at their body.
