7th Hour Kiddush During Permanent DST

Some people have the minhag to avoid making kiddush between 6 and 7. Among those with the minhag, there are some who switch to avoiding it between 7 and 8 during DST as that is the time frame that would be 6 to 7 if clocks didn’t change.

Personally, I already don’t understand the second camp. In theory, the issue is during the 7th hour after midday, but clock-noon is treated as the “average midday” rather than it shifting every week with zmanim. Furthermore, regions where clock-noon is nowhere near average midday (eg. areas far to one side of a time zone) still observe the minhag from 6 to 7 without adjusting.

Once the minhag departed from being connected to halachic chatzos or even the mathematical average and instead is based on 6 hours after when the clock happens to say 12, why adjust for DST? Why is that different than adjusting for region?

If a region switched to permanent DST, would even the second camp concede that the issue would be between 6 and 7, or would they forever switch to 7-8?