It has been a phantom product, because Apple has needed to fill major gaps in the desktop space first.
I suspect Apple is set to debut powerful revision to the Mac Pro focused on AI/ML at WWDC.
I wrote about this 10 months back[0], and it still applies following Studio:
> It may not be obvious, but Apple has repair work to do in the pro community. Four years ago this month, Apple unusually disclosed that it was "completely rethinking the Mac Pro." [1]
> The current Mac Pro design wasn't announced until June of 2019 and didn't hit the market until December 10th of 2019. That's just six months prior to the Apple Silicon announcement.
> It seems unlikely Apple spent 2017-2019 designing a Mac Pro that they would not carry forward with Apple Silicon hardware.
> The current, Gen 3 2019 Mac Pro design has the Mac Pro Expansion Module (MPX). This is intended to be a plug-and-play system for graphics and storage upgrades. [2]
> While the Apple Silicon SoC can run with some GPU tasks, it does seem it does not make sense for the type of work that big discrete cards have generally been deployed for.
> There is already a living example of a custom Apple-designed external graphics card. Apple designed and released Afterburner, a custom "accelerator" card targeted at video editing with the gen 3 Mac Pro in 2019.
> Afterburner has attributes of the new Apple Silicon design in that it is proprietary to Apple and fanless. [3]
> It seems implausible Apple created the Afterburner product for a single release without plans to continue to upgrade and extend the product concept using Apple Silicon.
Given "Ultrafusion" it seems plausible that M2 would be able connect multiple custom SoCs that are littered with GPU cores as stackable accelerator cards.
> So, I think the question isn't if discrete Apple Silicon GPUs will be supported but how many types and in and what configurations.
This prediction not come to pass:
> I think the Mac Mini will remain its shape and size, and that alongside internal discrete GPUs for the Pro, Apple may release something akin to the Blackmagic eGPU products they collaborated on for the RX580 and Vega 56.
But at least the mid market display now exists.
> While possibly not big sellers, Apple Silicon eGPUs would serve generations of new AS notebooks and minis. This creates a whole additional use case. The biggest problem I see with this being a cohesive ecosystem is the lack of a mid-market Apple display. [4]
[0] https://news.ycombinator.com/item?id=26956886
[1] https://daringfireball.net/2017/04/the_mac_pro_lives
[2] https://www.apple.com/newsroom/2019/06/apple-unveils-powerfu...
[3] https://www.youtube.com/watch?v=33ywFqY5o1E
[4] https://forums.macrumors.com/threads/wishful-thinking-wwdc-d...