Assuming they can build it (and they have implied that they can scale their silicon designs up in terms of cores, power, and clock rate), an Apple Silicon Mac Pro will be a pretty interesting machine.
If they wanted to, Apple could even bring back an Apple Silicon powered Xserve, or the legendary, mythical, modular desktop Mac (I know, now we're in the realm of pure fantasy, but one can dream.)
Given their performance/watt, this sounds like it could be potentially game changing.
The Gravitons are based on Cortex-A76 aren't they? Don't phones with that architecture benchmark similar to an Apple A10?
Amazon, Google, Microsoft each have a cloud offering.
The M1 is just what Apple needed to compete there.
The Vega II is even faster (but quite a bit more expensive).