I wonder how big will be outcry on this very forum if Apple will come up with anything similar to Corsair One computer

.
it is macrumors so some folks will complain that the sky is blue.
How big. Just about as large as it was for the Mac Pro 2013. If the default is an AMD GPU ..... the Nvidia fan boys aren't going to be happy. There would be some slight shift in complaint set if there was an Nvidia GPU. It isn't a generic off the shelf GPU replaceable by any random board. So the folks who are complaining about not buying stuff off the shelf would still be complaining.
Corsair doesn't have Thunderbolt, but I think does some video port redirect. Is Apple going to hide the "loop back" Rube Goldberg solution inside the case? .... probably not. So even less "off the shelf" GPU card than that. [ There are some other vendors that use a MXM GPU card but again will have folks moaning about it isn't a broad standard slot. ]
Only one GPU possible so the "need 2+ GPUs" folks will still complain. ( And Apple pretty much will be skipping a decent chunk of the folks they previously found that liked having 2 GPUs. There were aspects of the Mac Pro 2013 that did work with some. )
No empty standard PCI-e slot .... pages of complaints about that.
No 3.5" drive ... plenty of moaning and groan will occur on that.
No optical drive ... the relatively steady drip , drip , drip water torture crowd on that will be certainly show up also. Apple Macs walked away from internal optical drives almost a decade ago and folks
It isn't like the Corsair One hasn't made multiple appearances on these "waiting for" threads before. Won't change much if presented for the nth time.
P.S. AMD has changed their policy for Data Centers....
Well. The new team that is focused on selling hardware is starting to pull off miracles. 12.5% market share in Data center of GPUs. 5% CPU marketshare gained in 2018. AMD will have even better 2019.
Not particularly a miracle when simply just stop shooting yourself in the foot and your major competitor takes to shooting themselves in the foot instead.
AMD is primarily is simply just executing what they should be doing mostly on time. AMD shouldn't have walked/dug the hole they did for so long. ( going off to chase Seamicro ( ~$300M down the drain), chasing after ARM , squatting on the flawed design assumptions too long, going down tangents like SSD drives, etc. )
Now. Can you imagine that they come to Apple with deals on their hardware, and try to sell HSA? can you imagine, that Apple demands porting ROCm to macOS, as a part of hardware deal?
This is the same AMD that helped walk Apple into the 'corner' on the Mac Pro 2013 GPUs. AMD appears to be on track to do better over next year or so but it isn't like Apple hasn't had their fingertips toasted (if not burnt) by them before.
Apple demands ROCm to macOS? LOL. Perhaps if Apple
pays entirely upfront for ROCm to be porting. ROCm is at the stage right now where AMD shouldn't be pulling much of the core engine out to put in another another non-portable engine to power it. That other engine isn't going to help them on Linux or Windows so ....... not a big upside to that. ROCM is already on OpenCL 2.0 and should be moving to 2.1-2.2. Apple has no 2.0 and is even on edge of abandoning the sub 2.0 instances.
Apple has had every opportunity to join and formally support HSA for years and they haven't. Why are they going to start now? Probably going to happen.
Intel's GPU for for OpenCL 2.1-2.2 (including flatter address space support ) got coupled to the "Cannon Lake" GPUs. ( Gen 10) So it had to slide. It appears that Intel has decoupled that and coupled it to the Sandy Cove comes with Gen 11 (which is obviously incrementally past 10). I don't think AMD has the "huge gap" you are trying to imply here.
I can easily imagine this scenario. AMD finally has tech advantage over Intel. They have the position to make such deals with Apple.
It isn't just AMD hardware tech. AMD's firmware , thunderbolt boot support , design board spin up support , driver support assistance , etc. would all have to equal or past Intel also for Apple's requirements.
( having 'sexy' tech and lacking on other dimensions isn't helping Nvidia much right now. It wouldn't help AMD either. )
There is a plausible path for AMD right now but it isn't a sure thing.