That section says:
There are a number of possible ways that applications could use Well-
known URIs. However, in keeping with the Architecture of the World-
Wide Web [W3C.REC-webarch-20041215], well-known URIs are not intended
for general information retrieval or establishment of large URI
namespaces on the Web. Rather, they are designed to facilitate
discovery of information on a site when it isn't practical to use
other mechanisms; for example, when discovering policy that needs to
be evaluated before a resource is accessed, or when using multiple
round-trips is judged detrimental to performance.
I am guessing they consider “general information retrieval” and “URI namespaces” to exclude it.