The problem is that it is a lot of tiny cables, and a lot of chargers with them.
Additionally, it also protects the consumer by preventing companies from locking consumers into buying device-specific chargers at greatly inflated prices. It might even become common for devices to come without chargers: why have 10 chargers lying around when all your devices use the same charging connector?
But no, this is not true. The iphone charger is already USB. I use them with my Android phone all the time, and iphone users charge with my pixel charger. Those already interoperate.
I understand the e-waste and consumer protection argument for the charger (power converter), but why the cable?
Up until recently everyone used USB-A on the charger end, with a dozen different competing fast charge protocols. Chargers had the same connector, but they weren't fully interoperable. USB-C is slowly trying to fix this.
I completely agree that the cables aren't a massive deal. But on the other hand, if you are already standardizing chargers, why not do the cables too? Personally, I see no overwhelmingly good reason not to do it.
Because the connectors still suck and there's a ton of room for innovation. Imagine if we were stuck with USB-C forever, that would be bad. It's already worse than lightning as a connector for cell phones.
The default shouldn't be to place arbitrary restrictions unless there's a good reason not to. Governments should restrict behavior when the restriction is justified. It should be the EU government's responsibility to demonstrate that banning lightning cables is good, not the other way around.
Additionally, it also protects the consumer by preventing companies from locking consumers into buying device-specific chargers at greatly inflated prices. It might even become common for devices to come without chargers: why have 10 chargers lying around when all your devices use the same charging connector?