Jersey implementation of the rest-integration has been provided since MGNLREST-82 / 2.1, in order to support application servers which shipped with Jersey as JAX-RS impl, and for which RESTEasy caused conflicts.

Magnolia bundles come with RESTEasy OOTB and 95%+ runtimes are Apache Tomcat.
Meanwhile, validating Jersey library updates (e.g. via renovate) requires some effort/onboarding vs. proven gain. We could enrich usage metrics to know more, but at this point, in order to favor more streamlined Magnolia deployment images, I think it would make more sense to extract it to a separate module and put in on the forge / magnolia-community.