You seem to have a very naive understanding of the dynamics here. Making it a life finder mission would have taken two times longer and cost three times more, assuming it wouldn't have been cancelled long before that.
NASA is not in charge of its own budget. Neither it is, ultimately, in charge of what missions get greenlit. Sure, NASA is an inefficient organization in many ways, including planning and management practices that never seem to get better despite numerous reviews, but honestly it's incredibly difficult to be efficient when your bosses sit in the Congress. You don't want to know what NASA's Planetary Science division could have achieved in the last twenty years with all the billions that have gone to the boondoggle that's the Senate Launch System and its earlier incarnations.
NASA is not in charge of its own budget. Neither it is, ultimately, in charge of what missions get greenlit. Sure, NASA is an inefficient organization in many ways, including planning and management practices that never seem to get better despite numerous reviews, but honestly it's incredibly difficult to be efficient when your bosses sit in the Congress. You don't want to know what NASA's Planetary Science division could have achieved in the last twenty years with all the billions that have gone to the boondoggle that's the Senate Launch System and its earlier incarnations.