While I appreciated your source 1.) I doubt 99% of Europeans work during 3am - 9am 2.) At least there can be other reasons: 2a.) EU times and African times are basically the same and Africa has a huge population. 2b.) India is closer timewise to EU/African time zones 2c.) What are about posts afterworks?
" RL conversation topics in the Bay Area tech scene are entirely different from those on HN shows a massive divergence in userbase. " Any proof?
I assume the 3am-9am figure was in US Pacific time, in order to emphasize the difference from the working hours of people on the US west coast.
Sure, but that's 12-18pm CET, which is hardly peak EU work hours.
So what does "the majority" mean? 51%? Because that's just saying those 51% occur during EU/UK afternoons and east cost mornings.