If you can get used to the offsets (sometimes changing because of DST), surely you can remember to offset the time at which they start their day?
Keep in mind this is already something that you need to take into account in some places: CET spans from spain to poland. Spanish lunch break starts at 2pm: https://www.spanish-town-guides.com/Opening_Hours.htm
https://en.wikipedia.org/wiki/Central_European_Time#Discrepa...
I'd support UTC everywhere. Context matters in any case, so it wouldn't necessarily make things easier for meetings, and you'd have to adjust to the fact that "noon" might be at "5pm" (17:00) UTC and midnight at 5am.