I appreciate that we also only use one nostril at a time, which we can only do with two. It swaps every few hours, too!

Maybe a hole of the appropriate singular size would need more structural support to remain open and be in more danger of: collapse, blockage, insect invasion, or foreign object ingestion - or objects large enough to be guaranteed to do more lung damage.

nature knows what happens to big holes

Small holes can be stretched. Urethral penetration is a thing, and more often happens to vagina owners than penis owners.

Directional smelling to find the source. Like sharks or bloodhounds

Snot rocket bb