> Uncle Steve is zero hours ahead.

Uncle Steve is the same number of hours ahead that he has always been, and that's a thing that could be looked up just as easily as finding his time zone. I think the author is greatly exaggerating the degree to which time zones solve any of the problems mentioned. Uncle Steve might be on a different sleep schedule from me, regardless of whether or not he's in a different time zone.

Days of the week definitely become interesting in a global UTC system, but noon used to literally mean "the sun is at it's highest point". I suspect that people would grumble for a year or two and then forget that another system ever existed.