Those who don't learn from history are doomed to repeat it
This isn't another Y2K. This is another 2006, a deja vu all over again moment.
A little history - in 2006, the US decided to alter DST definitions from 1st Sunday in April through last Sunday in October, moving the changes to 2nd Sunday in March to 1st Sunday in November. Windows 2000 systems were pretty easy to address. Using an application called TZEdit.exe, one was able to enter into the time zone tables and adjust the DST definitions from there for your time zone, restart the system and all good. However, Windows XP had an embedded database that was not able to be edited in the same way. Ditto for newer server platforms. In this instance, Microsoft released updates via Windows Update. When dealing with Process Controls, including HVAC and building security access systems, time is a critical thing - devices need to be accurate synchronized together, and actions taken based on time definitions, such as building occupancy schedules, but certainly not limited to that, suddenly malfunctioned in environments that had no internet access and disallowed Windows Updates due to the damage these can do to front end SCADA software. To address this condition, downloading redistributable patches for XP (SP 2 and SP 3) as well as for Windows 2003 server were necessary and field techs ran around like chickens with their heads cut off trying to apply these patches to supported systems prior to the change taking effect. Turned out the time zone patches from MS were ineffective. New patches were released, which worked... for one year. If memory serves, it took 3 or 4 patches to get it right, and new operating system had the new definitions baked in, but will require similar work to address. I am sure similar success will be realized.
Then you have tech and travel. We have many time zones across globe, let alone 4 across the USA alone. Not all of them will change to follow our lead. This will unnecessarily create huge process controls issues across the board. And many of these environments are still using Windows XP, which hasn't been supported in eons, especially the CE edition, which saw support drop in 2020. Many HMIs still run on Windows 6 CE.
This is not a good idea.