> I can't think of a workflow that would be better served on a local mac with 1.5TiB of ram
I can think of a few, but they all involve terabytes of data sitting on local storage. At the terabyte sizes, it starts to take more time to transfer the data to the cloud instance than to process it with a beefy workstation.
all the workflows I can conceive of right now would struggle to use more than 128G of RAM, but I am open to ideas.