Section 6.1.3 contains the following statement. 

Producers of Knowledge Artifacts SHALL use Expressions of type text/fhirpath for defining Knowledge Artifacts. Producers MAY also create the same Knowledge Artifact using Expressions of type text/cql.

By stating that KA producers must use fhirpath you are mandating a defacto means to define these expressions that every backend service client will need to be able to process. This in turn makes including CQL as an alternative means to define the expressions irrelevant and pointless as you would already need to supply the fhirpath equivalent and backend apps will need to support fhirpath.  

CQL and FHIR path should either be on equal footing or one should be removed and the statement should read. 

Producers of Knowledge Artifacts SHALL use Expressions of type text/fhirpath or text/cql.identifier for defining Knowledge Artifacts. 

The change to text/cql.identifier in the statement above is to keep in step with the work that is being done elsewhere to call out when cql is just raw cql (text/cql) vs when the cql expression is an expression in a library (text/cql.identifier).  This is included in other R4 based IG in this manner as well as being included in the R5 specification