Have never understood the impulse to dunk on someone trying something new when it does not impact you in any way.

Some definitely comes from insecurity (as others said), but IMO the other half comes from overfitting from expertise.

Common HN commentator: someone Very Smart thinks new thing is dumb or obviously a scam. Anything crypto-related for example, like the Classic Smart Finance Person, or the Classic Smart Distributed Systems Person. Anything cryptography-related was another classic example that predates crypto, Classic Smart Cryptographer is very upset that someone dares attempt to improve on usability of Very Serious encryption workflow.