PSYC is an open non-standard. The meaning of open may require a definition.

Standards are overrated.

How high is the ratio of irrelevant RFCs compared to the relevant ones? What does it take to get an RFC through the IETF?

The TAO of the IETF says:

One of the oft-quoted tenets of the IETF is "running code wins", so you can help support the standards you want to become more widespread by creating more running code.

This implies, that something declared a standard by the IETF is still in competition with other "standards" of which some may win and some may lose. An RFC never means the Internet will start adopting that and only that, and everything else has lost for all times.

Most of the Internet's really big de-facto standards came from anywhere but a standards organization. See IETF for some non-examples.