[dwaite]

> Gone, thanks to EU legislation.

Sort of. Standardizing on a USB-A charger did slightly push people to use a USB form plug on the other end - but data transfer is what really killed the proprietary connectors.

The multitude of USB connectors has been pared down - mini USB was withdrawn due to its design flaws, micro USB was obnoxious for 5Gbps data transfer, as was the larger USB-B plug. The convenience and capabilities of USB-C have slowly replaced them both on the device side, as well as the capability to go higher than 5 Gbps.

If anything has slowed adoption of USB-C, I'd point at desktop PCs and the reluctance to put 'real' USB-C ports on them. This is mostly because of what I consider to be a design error on the USB-IF's part - they added backward compatibility, allowing a USB-C dongle to supply a USB-A connector, when they should have supplied forward compatibility instead. This left a lot of bundled cables as well as hardware dongles like wireless mouse adapters stuck on USB-A.