I did not intend to fat-shame, but I can see that's how I came across. Sorry. I'm binary, but a fat dude myself. Can you be fat and heroic? Definitely, both IRL and in fantasy. Mirt the Moneylender comes to mind (well, more fat & mercenary), and good old Friar Tuck is often portrayed as a heavy guy. I'm sure there's more. But I still see a difference between the lack of "fat & old" minis and the lack of "gender neutral" minis. You can be fat and heroic, but being fat is not aspirational. Not that our fantasy characters always have to be aspirational, but most often that's the direction we take. Being fat is okay and you shouldn't be shamed for it, but you should also working to remove that condition, for health reasons. If you are non-binary or queer, that is perfectly healthy and isn't a condition to work at removing or changing and can easily be a part of an aspirational fantasy character.
I'd rather see miniature companies work on expanding their non-binary and gender neutral offerings before other things. But ultimately, it would also be nice to see a wider range of body types; fit, fat, skinny, and everything in between. Fantasy art (and sci-fi, and superheroes) does tend to focus on art portraying a narrow range of body types, in both illustration and in 3D miniatures . . . the more we can get away from that the better.
As I mentioned above, I'm a fat guy, although I'm not sure about the heroic part. I've actually played a fat & heroic character once (I usually don't), and the character's weight was a part of his backstory, how others treated him and how it made his new life as an active adventurer difficult at times. It helped me work through some of my RL issues with weight, to both accept my body without shame, but also to strive to lose weight and improve my health and fitness.