When I worked at a national laboratory, it was always evident that research priorities lagged funding priorities. No scientific program director would allocate significant resources into an area that wasn't either already funded or practically guaranteed to be funded. I don't how NASA and JPL operate organizationally, how their budgetary decisions are made, but I would guess that no movement toward re-orienting around Starship (or any new commercial technology) will happen until funding agencies dictate that it happen.