Why would they remain fundamentally expensive? It is a fixed machine (so eventually you recoup the investment) and running consumes nothing other than electricity and a paper gown. MRIs cost under $200 in Japan.

Yes totally, and ultrasound already does wonders in that regard. It's a good strategy to focus on the specific use cases that match the strengths of the tech. I think MRI will be useful in validating and mapping out those cases.