Except the marked did not do that on its own.

The EU gave the industry an ultimatum in 2009: Adopt a common charger voluntarily or we'll regulate to force you to do so. Almost all manufacturers did, first with micro-USB before moving over to USB-C.

Eventually, because Apple decided not to play well with others, they had to follow through and regulate.

lol. do you remember times before microusb? which was also somewhat forced by the EU? so no.. the unification on the USB wasn't all pure force of market...

Yes, because some actors don't want to follow suit.