You keep on defining things in terms of cultural artefacts that are simply not consistent even in
one area, let alone worldwide. A 9–5 work day, a meal called “lunch” that concluded by 1pm—well, I seldom eat lunch before 2pm (and 5pm is not uncommon), and I know people who don’t have any meal that would match the description or schedule of “lunch”.
9–5, 9–6, 8–4, 7–3, 11—7, these are all common in different places, and outliers with far less overlap—perhaps even none—are common. And that’s just for office sorts of work; count other types of work and especially asynchronous remote work and the disparities get far more extreme. I know full-timers that will be working from 6am until before 3pm, and others that will be working from 6pm until 3am. And latitudes and seasons affect things drastically too.
Look, time zones give you some hints, but they’re really pretty weak hints.
