a) Universal Resource Locator (URL), with standard form. The URL format should be used whenever the referenced definition is known to be electronically available using this standard URL.
b) Universal Resource Name (URN), with a specified form. The URN format shall be used whenever the referenced definition is not, or might not be, available using a URL. This URN shall reference data that is specified by some ‘authority’ and is ‘well-known’ to both client and server software, including multiple clients and multiple servers.
That's incorrect, the U in URL and URN stands for Uniform not Universal
In A.2. URNs for Coordinate Reference Systems of https://docs.opengeospatial.org/pol/09-048r6.html#toc23
We have
That's incorrect, the U in URL and URN stands for Uniform not Universal