my issue will reside in when people know they have this objectively bad thing about themselves and refuse to do anything to fix it.

why is this an issue for you? Why do you care? Why is it an "objectively bad thing" what people do with their bodies? Would you call someone a "smoking fuck" or a "tattooed fuck" or whatever? What's it to you? Also you don't know what a fat person "working on themselves" looks like. For instance psychological trauma can cause someone to become fat and that person might be unable to get to a societally acceptable weight until that trauma is resolved. Which might be impossible due to other factors.

There are so many facets to this that you cannot possibly know or comprehend unless you have very close fat friends or are fat yourself.

Not to mention that your judgemental attitude makes it harder for someone to lose weight. One of the reasons fat people don't like to jog or got to a gym or really be in public at all sometimes are the judgemental looks and attitude they get even when they do what everyone expects of them: losing weight.

Also there just are different body-types, and not just the one that everyone expects. I don't know if you have spent any time around babies but they look all completely different in terms of how fat they are and it isn't due to diet, or lack of exercise, they were literally born that way. Why should this be different for adults??

I will always judge the first group, because everyone should have the self realization to try to be a better person.

A thin person is not "a better person" because they're thin fuck off with that.

Just let people be who they are and don't expect them to become acceptable to you. That's a really shitty thing to do to others.