On 9/22/21 12:34 PM, Tom Lane via tz wrote:
1. It's not possible to separate the new backzone zones from the old.
No, actually it is possible. I've done it, by using the patch I described here: https://mm.icann.org/pipermail/tz/2021-September/030456.html That patch does exactly the separation you describe. It separates the new backzone Zones from the old ones. When using it, I obtained tzdata.zi and TZif files that exactly matched 2021a except for the changes you're not objecting to. I verified the match by zdumping the resulting TZif files and comparing the outputs. This all took quite a bit of work, but it was work I was willing to undertake to avoid the (to mind worse) alternative of forking tzdb.
2. This approach puts it on individual tzdb distributors to decide which of these two options to choose.
Yes, that problem is inherent to any fork or option-equivalent-to-fork. That's one reason I recommended against using the patch. Another reason - more important to my mind - is that sticking with 2021a's blueprint would mean that its equity problems would remain present in whoever uses that blueprint.