Responding to Yaroslav: I think that this is a bad advice. First, even though the headquarters for Wolfram Reserch is, indeed, in Illinois (hardly a backwater), the company itself is about as global as one can get.
Second, for the most part, Wolfram Research has been a leader in new technologies, from support of the GUI in Next and Macintosh, to the development of Wolfram|Alpha.
Third, while Apple sometimes tries out new technology (OpenDoc, Touch bar, etc.) that it later abandons, the use of Metal is now almost 10 years old, and is a matter of active development. Further, it would be in Wolfram's interest to make use of Apple's APIs, since they isolate the code from the hardware.
Fourth (and this relates to #3), NVIDIA may be the leader, but the technology is hard to work with and breaks frequently. (I used the technology when Apple used NVIDIA).
Now, I have something at stake here: all my computers use Apple Silicon, and I would really like to be able to use the option "UseGPU" and have it accelerate my computations. Based on what I have seen on the current implementation in Mathematica, it would certainly be worth the effort.
I am sure that there a lot of people who would like to take full advantage of things like Machine learning and neural nets that would benefit from using the Apple Silicon GPUs, but who would rather not have to learn the low level nuts and bolts, or, perhaps do not have funding to invest in a lot of extra hardware.
Recent comments from Stephen seem to indicate that taking full advantage of the new Apple hardware is under active development at Wolfram, so I am hopeful that some version of Mathematica (maybe even some version of 13.x) will do what we want.