Yes, it's conjecture. I explicitly, outright said it was an unproven anecdote. Demanding citations when I'm explicitly giving a "feel" narrative is misplaced and not charitable.

As to how many uniques you can expect from a front-page on HN, go ahead and search. Pre-2020 you can find countless people detailing 30,000+ uniques in the first few hours (my own, personal, direct experience was 50,000+). Now, if you average out more recent reports, you can expect about 11,000 over the first 24 hours.

And sure, the most inclusive possible discussion gets a few hundred comments. Everyone wants to put some paint on the shed. There is a 4 hour old submission on the front page with 2 comments. Eh, guess it doesn't represent much.