Standardization would help!
major players are close, but not all onboard.
the evolution was slower decades ago.
early 70’s everyone used 120 mm rear spacing then 6 cogs came in to get that 13 without sacrifice.
Index, but there was a friction option
then, 7, then 8- Shimano and Campagnolo rarely on equal spacing on the run up to11
11 was pretty close...
are the Campag teams running 12 now?