But what's the actual value proposition of having a simple regular calendar if all of the important dates that people care about move around on it all the time? Sure, maybe you always know what date it is, but now you don't know what's happening on that date. The end result is the same level of complexity, it's just that now the date numbers are useless.
> all of the important dates that people care about move around
What dates do you care about?
I know my calendar is full of one-off events, and the recurring events follow the calendar, not the seasons. For these, a 6 day week/30 day month would be easier. That weekly Monday meeting? Always on the 1st, 7th, 13th, 19th, or 25th. The next federal holiday? We can make those always fall on a Monday if we wanted.
I can see that the start/end of the school year is important, but that already moves around enough that you need to look it up. If you are looking for best dates to take a beach vacation, yes, you'd need to look at the seasons.
Or wants annual holidays to predictably fall during a certain season.
"Grandpa, what was it like in the days when it was cold outside during Christmas?"