Validate need for javax.resource.api / javax.xml.bind.api package declarations in ee layer

Why do we have this:

https://github.com/wildfly/wildfly/blob/27.0.1.Final/ee-feature-pack/galleon-common/src/main/resources/layers/standalone/ee/layer-spec.xml#L8-L14

JavaEEDependencyProcessor adds optional deps on those modules to deployments. But why do we need to declare optional packages in the layer? AFAIK since they optional they won't be provisioned in a slimmed server, and all modules are provisioned in complete installation, so what's the point of that stuff in the layer?