They picked wrong.
They should have picked Standard Time.
As someone else pointed everyone is already on DST for approximately 65% of the year. This just removes the remaining 35%. Picking standard time would have been a much bigger change.
Ultimately, it's entirely arbitrary anyway. The only issue is that American states cannot pick DST without a federal law change.
> As someone else pointed everyone is already on DST for approximately 65% of the year. This just removes the remaining 35%. Picking standard time would have been a much bigger change.
This 65% started during the Dubya presidency (source: I was there updating tzdata on systems), and previous to that it was a 50/50 split.
So 65/35 or 50/50 is arbitrary.
But the reasoning for that was a preference for DST.
Obviously all this is arbitrary including standard time.
> But the reasoning for that was a preference for DST.
There was no reasoning for the Dubya alteration: the change was not debated anywhere, and (AIUI) no one was ever able to figure out how it actually got slipped into the legislation.
The DST extension was included in Section 110 of the 2005 Energy Policy Act, debated as part of the bill, and justified on energy-savings grounds. Congress even required the Department of Energy to study its impact afterwards!
Metric time would have been better.