[fredoralive]

Possibly just to avoid having programs that rely too much on specific implementation details of the current engine causing issues in the future if they decide to change the hardware design? An obvious comparison is graphics cards where you don't get low level access to the GPU[1], so they can change architecture details across generations.

Using a high level API probably makes it easier to implement a software version for hardware that doesn't have the neural engine, like Intel Macs or older A-cores.

[1] Although this probably starts a long conversation about various GPU and ML core APIs and quite how low level they get.