That's just BS. My Mac doesn't do anything when a USB device is attached, and that's the most non-technical user population in existence.
If there's any uncertainty that the computer has recognized the peripheral, then THAT is a major bug in the operating system. You only need confirmations when you have to constantly worry that the computer has failed.
A better notification would be "A USB device was attached, but the computer doesn't recognize it. Sorry." But to pop up a notification for success of peripheral attachment is just dumb.