F5 with new architecture, and eventual migration away from TMOS is going down the tenant path. We already saw a bit of this with iApp templates creating folders for applications, and new FAST templates using tenants a well.
One can "resist" or migrate to this new methodology and accept it, lol. If you want to "resist" you could always develop a parser in Python to search and replace object names and references. You can also do this manually. Or you can migrate to the new way.
Finally, you can submit a feature request to the Journeys page. Alternatively, you can use your sales engineer / partner to champion your case with F5 to implement the required functionality and prioritize any RFE.