I note TFA mentions 'normal' people 8 times, but never uses the word 'average'.
Whereas I think they are in fact describing 'average' people.
I suspect most HNers self-assess as normal, but are also self-aware enough to acknowledge (rightly or wrongly) they're not average.
Certainly I have felt overwhelmed with the 'why have they broken so many conventions?' sensation with, invariably, audio apps on microsoft platforms - but OTOH the implied expectation that all software should have a comparably broken UI as mildly modern microsoft word versions expresses a collective poverty of expectations.