You're incorrectly generalizing from yourself to most people. Most people think in local time and would continue to do so regardless of whatever you attempt to do to impose something else on them.
Also, think of how deleterious the abolition of local time would have on communication. Right now I can say something like "I received an urgent call at 3am" and you know immediately what that means. But if I said "I received an urgent call at 17:00Z", a lot of the meaning is lost. You'd have to know where I live, i.e. what my local time zone is, and then do some quick mental math to determine what actual time of day 17:00Z means for me. With local time, that calculation is already done for you! Local time is just too damn useful of a concept. It really truly is better than global time for most uses. Global time is really only useful for scheduling global meetings and computer stuff. Even within the US, all of our scheduling is done by US timezones.
Also, think of how deleterious the abolition of local time would have on communication. Right now I can say something like "I received an urgent call at 3am" and you know immediately what that means. But if I said "I received an urgent call at 17:00Z", a lot of the meaning is lost. You'd have to know where I live, i.e. what my local time zone is, and then do some quick mental math to determine what actual time of day 17:00Z means for me. With local time, that calculation is already done for you! Local time is just too damn useful of a concept. It really truly is better than global time for most uses. Global time is really only useful for scheduling global meetings and computer stuff. Even within the US, all of our scheduling is done by US timezones.