It is striking how many timezones are all red instead of being split red and green. In my childhood, people always talked about how different the evening/night culture was in Spain with meals at late hours. This map tells me the difference is less significant than I imagined as far as solar life, and more due to the time standard.
While this topic is beat to death already, I remain torn. On the one hand, centering on solar time is the only logical criteria I can see for adjusting and revising standards. To revise it even further away seems illogical to me. But, the map clearly many cultures already have gone that route. I can imagine many of these deviations came from some legacy desire to synchronize with an adjacent center of power or commerce. I can also appreciate that if we set it far enough out of whack, it illuminates how any standard is inherently arbitrary.
FWIW, I think that map is from the time when Russia tried permanent DST from 2011 to 2014[1]. They changed to permanent standard time after it proved unpopular.
Regardless, there's no purity to be had here. No matter what, time zones themselves are a compromise for the sake of practicality -- there's no inherent virtue in "the sun is at precisely peak at 12pm +/- a geographic offset."
You can find a pretty good visualization here:
http://blog.poormansmath.net/images/SolarTimeVsStandardTime....
This shows the difference between solar time and standard time. By switching to DST you essentially shift the gradient to the east by an hour.
Other than Greenland I can't see a timezone where that wouldn't mean that the longitude at which the difference is 0 is outside of the actual timezone.