It's important to remember that one can become stuffy and lose their sense of smell for many reasons. Seasonal allergies can cause inflammation of nasal sinus tissues and that can retard your sense of smell.
You know what other sense smell affects? That's right, your sense of taste.
Lifetime of seasonal allergies until I cured them, NEVER had a single event/illness causing loss of taste/smell like I experienced this weekend.
As I commented a few minutes ago, it’s to remain a curiosity & unresolved, but appreciate the feedback.