I think darlindeb's sleep doc is wise.
I wince every time I see "mild" listed on a sleep study interpretation (I work in the office of a sleep lab). I will be asked to schedule patients to return for a titration. The patients often ask for specifics about their first sleep study. I usually look at the sleep study report before calling to schedule the titration. If the report says "mild," I won't say that to the patient. I know that the patient may think that "mild" means they don't have to be treated. If I know they're listed as "very mild" and they're reluctant to be titrated, I will schedule them to meet with our sleep specialist, a pulmonologist.
It's a vague scale, and often overused. And the scale varies slightly from lab to lab. Plus you can be "mild" overall, yet "severe" during REM or while sleeping on your back. Plus other factors describe your condition. A person with an AHI of 10 but averages 20 seconds an apnea when they're not breathing might be a little worse off than someone with an AHI of 10 but averages 10 seconds of not breathing. Plus, there's how long you likely had the condition, the levels of blood oxygen, and of course your symptoms. And, your untreated sleep apnea may have affected your heart and other health areas, for which struggling with a mild apnea is still serious.
I suspect the scale was used in part to flag those who are very severe, ones who are in more of an immediate danger, a kind of comparative thing. But as was said, whether mild, moderate, or severe .... it's still sleep apnea. Personally, I hate the term "sleep apnea" because it's misleading. It's not a sleep disorder.... it's a respiratory disorder (it just happens during sleep). Which sounds worse to you -- a sleep disorder or a respiratory disorder? So if you stop breathing a little or a lot, it's not good to be not breathing!
Don't get hung up by the scale descriptions; concentrate on your symptoms and your health.