A brain is more energy efficient than a chip, but how a couple of cells connected to wires has more economic sense than a chip with gallizions of transistors?
This is closer to rent a transistor, and the main use case is to find out what its voltage curves are.
It is not a computer.
I did work on a version which used in vivo brains for actual computation. It worked but no one wanted to invest in building the matrix for rodents. With the benefit of hindsight I shouldn't have added the slide explaining ethical considerations: 'Container Labs in international waters help us manage regulatory risks'.
Yeah. My understanding was that you'd need constellations of neurons to achieve a complex result, rather than a couple individual ones. Perhaps this article is light on details and it's more involved.