Don't think of it as a standard as-in SAE, but a standard as in "molex", "AT", or "ATX". Yeah, they aren't really "standards", but they aren't exactly proprietary either and they also are clearly useful.

The goal seems to be to promote reuse of a good-enough design in as many places as possible. Noone's forced to use it, but it'd make things simpler for everyone if there is as much commonality as possible.