Other peoples obesity and diabetes does not place someone else at risk as these are not communicable diseases so these aren't apt comparisons. The whole minorities and gunshot argument is simply too ridiculous to comment on. But I will say it is also strange to say that gun control doesn't work when there have been no meaningful gun control restrictions that have been placed into law, but that is an entirely different discussion.
If you want to make the case that certain groups should pay more for health insurance for poor lifestyle choices (smoking, obesity, etc), I'm all for it. Why should I pay more for health insurance because (the proverbial) you wanted to smoke for 50 years. I personally think the same should be said for those who refuse to be vaccinated for COVID. I can guarantee that insurance companies currently have actuaries looking into this and I certainly would prefer those who are unvaccinated to pay more for their insurance. Why should I pay for your poor choice? If you work for the federal government (or you are contracted by the federal government) and you don't want to get your required vaccine, you have the option to find a new job. Remember, you aren't being fired, but you quit based upon your beliefs. Same goes for any private sector employer. Why should they risk their employees being absent from the office, factory, etc. because people didn't want to get their vaccine. It will cost them money and drag down the economy if large portions of their employees are out sick. I am betting that once people are shown consequences for their choices things will change. But if people are fine with having their employment opportunities limited and paying higher care premiums so they don't have to get the vaccine that is perfectly fine with me.