80% of Covid patients experience anosmia (loss of smell), and 10-20% of this set experience longer term effects known as parosmia, or a damage to sense of smell. Scientists explain this is essentially due to mixed up wires (aka faulty nerve repair) between your olfactory and brain. As a protective evolutionary tactic, the body conservatively re-establishes said linkages; for example, french fries might smell like rotting meat. But this begs the question, if alcohol is technically a toxin, what does whisk(e)y smell like?!
Regardless, with about 350 receptors, sense of smell is an integral part of human life. This article outlines fascinating insights into Covid-19's effect, and what the road to recovery might look like.