[tz] [PROPOSED] Merge timezones that are alike since 1970

[Paul Eggert]

On 5/29/21 2:00 AM, Stephen Colebourne via tz wrote:

>> > Why should we maintain Norway and Sweden's
>> > time zone histories, when we don't maintain the histories for
>> > Guangdong, KwaZulu-Natal, Thanh Hóa, or Uttar Pradesh?
> 
> Because they are regions of the same country!

Thanh Hóa is not in the same country as Bangkok (Asia/Bangkok's 
most-populous location).

> merging zones across modern countries isn't acceptable.

The practice is clearly acceptable, as tzdb's zones have crossed 
national boundaries for decades in some cases (as I mentioned in an 
earlier email). Unfortunately we haven't been consistent about this, and 
our lack of consistency has led to understandable charges of political 
favoritism.

If we insisted on creating a new zone every time there was a different 
country, we'd have a more-complicated database and get into even bigger 
political messes than we already have. There was an example of this 
recently in the complaint about why there is no separate tzdb entry for 
Kosovo. I endured quite a bit of vitriol in private email about this.

In the long run we are better off decoupling tzdb entries from political 
issues as much as we can. This will lessen the probability of similar 
vitriol (or worse) in the future.