A single university or even department could make this change - reproduction is the important work, reproduction is what earns a PhD. Or require some split, 20-50% novel work maybe is also expected. Now the incentives are changed. Potentially, this university develops a reputation for reliable research. Others may follow suit.
Presumably, there's a step in this process where money incentivizes the opposite of my suggestion, and I'm not familiar with the process to know which.
Is it the university itself which will be starved of resources if it's not pumping out novel (yet unreproducible) research?