It’s only anecdata but until I tried tri-fold N95s I couldn’t find a bi-fold to seal to me half so well as the KNs, leaving me dependent on my elastomeric. So there may be at least a few cases where that’s the better-fit option.
None of that makes sense of Mr. Dangling Strap, though. Maybe he was sipping water a moment before (not ideal but understandable.)