Although I have not contracted covid, one of my best friends is currently afflicted, and his description is anything but mild. He's very fit (daily mountain bike rides, etc.), non-smoker, light drinker, etc., and he describes the symptoms thusly: "The coughing has been so bad that every muscle in my body aches and my
lower back is sore. The body aches are bad regardless of the coughing
and I wouldn’t call any of this mild. Advil didn’t touch the muscle
soreness last night. I needed to cough but it really hurts when I do. I
started feeling a little bit better this afternoon but no energy and
little appetite. The sense of taste and smell is gone. So coffee just
tastes like very bitter hot water."
Mostly he's mad that he's lost a couple of weeks of his enjoyment of life, and at age 63 it'll take a couple more weeks to get back to his previous level of fitness. That's not insignificant when one trains for seasonal sports, such as the forthcoming ski season, and tackling the highest extremes of the endeavor can be dangerous if not in peak condition.