Why resist the idea of long covid, which now has an actual medical code, when lack of smell specifically is symptomatology of only covid esp since it all started with covid? Please check out the long covid section and see what else is there you font even realize. I have had long covid for 3 years and 2 weeks. (Whose counting?) I've had every test and CT scan etc there is. I got kidney stones for the first time in my life. My voice is an octave lower probably from inflammation of my larynx they say as a chronic autoimmune pain disorder spread from covid.
You can keep looking like millions of us have, and do to satisfy as ywo things can happen at once and increased inflammation (how covid attacks the body) can get many other things going.

Lack of smell is why you have lack of taste. How aboit bad taste that many have? Fatique where a 35 year old marathoner can no longer walk to the bathroom. I now have POTS from covid.

Keep looking but also wonder why you aren't willing to go there? Does it feel futile? Yeah, long covid is. Nobody cares about us anymore. People don't want to believe its real there deny. A friend says she has a horrible new allergy for 3 years...hmm. hope you discover what's up so you can get care or acceptance and both whatever it is affecting your health so badly. I empathize.