But does that mean that UTC time will diverge from common time zones by more than a fixed number of hours (and minutes for a few esoteric time zones)?
But because the sun's trajectory changes throughout the year, and we live in very coarse timezones already, it was always a bit useless tracking this with seconds precision.
The solar noon never happens at 12:00 anywhere anymore. We've left that era about 200 years ago when we synched clocks with the capital city for the benefit of train schedules.
P.S. Well, technically the solar noon happens at 12:00 in New York on January 2nd, Chicago on Jan 14, Denver on Dec 25th, Los Angeles on Jan 9, etc. (on other dates, it's off.) In Santiago de Compostela — where they want to be on the same clock as Warsaw — solar noon happens as "early" as 13:18 and as late as 14:40.
If so I'm failing to see how this is less likely to cause bugs