Once you get in shape and look better you’ll suddenly WANT to promote your music.
I was obese for the most apart do my life. For the music part of my life I was obese for 7 years. I lost significant weight. Got better skin and clothes. For the past 6 months. I gained more listeners and average listeners per months than the previous 5 years of my carrier. It might be because of looks but I also almost didn’t promote myself at all.
I think we worry how we look like in other people eyes and too self conscious about it. And of course people judge by how you look. But if you put music first and your “image” after I think people generally don’t care. Just have something worth remember about you. It doesn’t need to be looks. It can be your lyrics your arrangements or soundscape.