For most people with sleep apnea this may be true. I didn't dive into the details but for a subset with UARS, people are typically thinner, younger and fitter. This group suffers from structural issues. In my case congestion and allergies. For others bone structural and require MMA or MSE to treat.

You did cover this in your article : )

It's both in the submission and in the Wikipedia article about UARS: "A typical UARS patient is not obese"

As far as I understand it, obesity can aggravate sleep apnea, but actually does not cause sleep apnea, so it is not at all the main cause. For obstructive sleep apnea, say, if you had a perfectly formed jaw, teeth, airway, etc., you could get obese without having sleep apnea.

Which means that obese people shouldn't rely on losing weight as a sleep apnea cure, as obesity is indeed not the main cause, but can likely see reduction in sleep apnea symptoms with weight loss.

Your understanding is wrong, obesity directly causes sleep apnea.

> There is a linear correlation between obesity and OSA. In obese people, fat deposits in the upper respiratory tract narrow the airway; there is a decrease in muscle activity in this region, leading to hypoxic and apneic episodes, ultimately resulting in sleep apnea.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5836788/

That's just plain false. Obesity is not the main cause of sleep apnea.