Are you old enough to remember the early 2000s when every phone and portable media player had it's own charger, which often wasn't even transferable between devices by the same manufacturer? It led to lots of old chargers when devices were replaced, which were useless for anything else (I remember having bags of cables and chargers). And if you wanted a second charger for whatever reason (this was before you needed to charge your device every 3 hours), you needed to find the specific charger for your device. If it was a few years old, it might not even be possible to purchase one.

Then almost by magic everyone switched to micro USB. You could charge different devices from different manufacturers with the same cable. This wasn't some feat of magic, it was because the European Commission worked to bring manufacturers to an agreement on a common charging standard.

Well, everyone except Apple, who did actually sign the agreement. They just decided to bundle a dongle to be compliant.

Mini-USB was introduced in 2000, so manufactures had plenty of time to choose a common interface themselves, but decided not to.

Even amongst Apple's own devices it is a mess. To charge an Apple Pencil with an iPad Pro you need not one, but two adapters.