Sure, but I work across three timezones, and I can glance up to the top-right of my computer and see all three at a very quick glance, as well as knowing when people are likely to be having lunch, whether it's early or late for someone, and so on. I'm also now quite used to "Jerry gets up early his time" for certain coworkers.

I guess you could potentially have some sort of graphic to show the same thing for sunrise vs sunset ... but as you point out, the maths needs to be done either way, so why get rid of a system that works pretty well?

DST is the real enemy here.