1/ A single world-wide time zone won't work as I think you think it will work. At least while we care about daylight. Imagine you need to know what are business

1/ A single world-wide time zone won't work as I think you think it will work. At least while we care about daylight. Imagine you need to know what are business hours for someone in other region. E.g. you business hours could start at +9 single world-wide time zone, but other person's hours start at +23 SWWTZ. You are back at having timezones. 1.1/ Besides, we do have UTC. And people already use it for coordination of global events. 2/ Substituting writing system with IPA will break a lot of languages. Especially Chinese. English will branch out into dozen hardly interchangeable writing variants. With time it will get worse.