It could happen, but from Apple's own announcements it seems like they were worried that the Mac was increasingly marginalized as a platform for AR/VR development, which Tim Cook constantly tells us (for AR at least...) is something he's super excited about for the future of computing. Not arguing this is the sole reason, but it definitely seems like a feature to cover high end edge cases like this for the time being.
Much of Apple's own discussions on the eGPU feature at WWDC/the marketing blurb for their own eGPU devkit refer to VR a lot too. Apple added VR support to Final Cut Pro at roughly the same time as well.
> And they seem to generally "dislike" putting discrete GPUs in laptops, going all the way back to the Titanium G4 days.
Not so sure I'd agree with this - every single Titanium PowerBook model ever made had a discrete GPU. Even the iBooks had dedicated GPUs. It wasn't until the adoption of Intel processors that integrated GPUs was even an option for Apple really.
>> it seems like they were worried that the Mac was increasingly marginalized as a platform for AR/VR development
As well as ML development, which is a pain w/o a local CUDA-compliant GPU. Yes, you could do it on the cloud, but sometimes it is easier to do ad-hoc stuff locally without having to spin up GPU machines and remember to spin them down.
>It could happen, but from Apple's own announcements it seems like they were worried that the Mac was increasingly marginalized as a platform for AR/VR development, which Tim Cook constantly tells us (for AR at least...) is something he's super excited about for the future of computing.
Because it is. High end AR/VR is exclusively DirectX Wintel 64 based. There's pretty much no exception except for the toy implementation of things like Samsung Gear. Google abandoned Tango, and Daydream is on life support. Apple's ecosystem will remain irrelevant until they release their own hardware.
For software sure. VR video content production is still a thing as well though, and plenty of video creators use Apple platforms. I imagine it was no accident FCP gained VR support shortly after the eGPU support announcement.
It's very pricey, but Apple sells an 18-Core 2.3GHz Intel Xeon W in an iMac with a 27" 5K display and a Vega 64 GPU, and up to 128GB of 2666MHz DDR4 ECC memory.
So while that is not a cheap option, Apple does sell powerful hardware. That's a decent AR dev machine, surely.
In the PowerPC days, they didn't really even have the option of an integrated GPU though. Even Intel's GPU that was integrated into the north bridge didn't come along until 98. And it was more of a cheap option for desktop fleets rather than a power conscious chip for laptops.
I'm skeptical of relying on eGPUs for high end VR. TB3 can easily choke the GPU and cause stuttering/framedrops, and missing any frames in VR is a recipe for nausea.
If Tim Cook is actually concerned about the Mac being marginalized for AR/VR, he'd get a lot more bang for his buck out of not treating OpenGL and Vulcan like the red-headed stepchildren on macOS.
"... it seems like they were worried that the Mac was increasingly marginalized as a platform for AR/VR development ..."
If, by "worried", you mean: they went out of their way to smite and thrash the organic core of their customer base, ignored their most basic requests, and deleted five years from their product lifecycle (nobody used the trashcan mac pro) ... then yes, I suppose they might be worried.
Maybe they noticed how many copies of High Sierra are running on firmware-modded 2009/2010 mac pros ?
Much of Apple's own discussions on the eGPU feature at WWDC/the marketing blurb for their own eGPU devkit refer to VR a lot too. Apple added VR support to Final Cut Pro at roughly the same time as well.
> And they seem to generally "dislike" putting discrete GPUs in laptops, going all the way back to the Titanium G4 days.
Not so sure I'd agree with this - every single Titanium PowerBook model ever made had a discrete GPU. Even the iBooks had dedicated GPUs. It wasn't until the adoption of Intel processors that integrated GPUs was even an option for Apple really.