I had the virus. This happened to me. The loss of smell and taste is as if someone completely cut off that function from your body. No stuffy nose during the illness, pre, during or post. It started coming back after about a week.
Isn't that due to mucus buildup in the nose? I think Covid doesn't have that.
It's a possible symptom but not a primary symptom, at 30~40% the anosmia seems way more frequent than nasal congestion.
I had a cold once that led to a total anosmia that lasted for over a week after my nose had cleared. It was very disturbing. I couldn’t smell anything at all. Not peanut butter, ammonia, gasoline, anything. Then like a light switch it all turned back on.