That's easy. We want well documented access to the low level device features. Any address-translation-layer should be optional at most.
The hybrid drive that is part SMR and part non-shingled sounds like a neat idea. But if I had one I would want to be able to address the two parts directly, and know how much and at what alignment I need to write to the SMR section.
Then we can do whatever mapping is needed in Linux, maybe in the filesystem, maybe in a virtual block device, maybe both. And different people can try out different approaches.