Why did apple have a 30-pin dock connector if USB can do everything?
https://www.reddit.com/r/apple/comments/yxrfu/comment/c5zw18d/
Why does Apple have a 30 pin connector anyway?

USB is a stack of protocols which is over complicated. Many USB implementations are riddled with bugs and people are used to just "disconnect and...

reddit
@SwiftOnSecurity in the middle of a industrial embedded USB deprecation because of this
@SwiftOnSecurity sometimes field techs need to plug in a usb, and if the device has been on for months, something fails to recognize the connection and requires a reboot, but it’s been on so long because it needs constant uptime, so my coworker had to sit at 3am while a team rebooted it in the middle of the night to make usb work again
@lampsofgold @SwiftOnSecurity I wonder how much of this is endemic to USB as a spec (not that you need to follow the spec) or is a problem of the USB stack implementation (assuming, via a miracle, everything else follows the USB spec)