Go read that
babyonian link for how easy large-base systems are to use IRL, you just teach kids some basic algebra rather than rote tables. Well, some algebra
and some rote tables, but not too big. NB: Base60 is written in alternating Base6 and Base10, but that's the same as base60 as far as math cares.
Ah. Base 12. Mmmm. 12's a nice number, and boxes of 12 items tend to stack nicely, but base12 is a bit rubbish anyway.
Different bases give you prime factor divisors that work, and prime factors of numbers adjacent to the base that
almost work in a memorable way. Quick ways to check for even divisibility apply similarly.
Base12 gets you 2 and 3 (and 2 again to make life tidy), and nearly gets you 11 and 13. Base10 gets you 2 and 5, and nearly gets you 9 (thus 3) and 11.
So base10 has a mess for /7 and /13, while base12 has a mess for /5 and /7, thus, the base12 mess turns up more often and notably earlier. All higher primes are similar messes, and no one cares anyway, you just don't divide things by 17.
Base30 (or 60, or 360) catches 2,3,5 but misses everything higher. Technically that's better, because you make a lot of numbers out of 2, 3, and 5; but 3's are easy in base10 anyway, it's just annoying to write thirds in decimal notation.
Interesting that a society which developed around base12 would view 5 as an awkward number to work with, and ascribe 5 and 7 magical properties as we do 7 and 13. Instead of 7*8 being the tricky point on the rote table, it'd be more like 9*A.
The big Y1K scare would've happened in our 1728. 265 days per 10-month year. 260 degrees in a circle. Pi = 3.184809493B9186 ... We'd have kept more of the old systems notation when they standardised the weights and measures. Number pads would look different. Musical notation would be easier to read. 6-digit phone numbers last longer. Instead of a 166MMX on a 33 MHz bus I'd have owned a 47MMX on a B MHz bus. No one would have ever made a d10 as anything other than a curio, and D&D would be played with the platonic solids only. Random tables would all have 144 entries.
PC, SJW, anti-fascist, not being a dick, or working on it, he/him.