[pjmlp]

Except SYSCL also works on AMD and Intel, and also has a CUDA backend, but apparently you missed that part.

In what concerns commercial uses of CUDA, Hollywood doesn't seem to have any problem with it, nor the car manufacturers with Jetson.

[TinkersW]

SYSCL might be an option, but it doesn't seem to have much in the way of adoption(Forum is dead)which is concerning.

It does look like Intel is supporting at least, so maybe in the future it will be a good option.