First, the Mini has free PCIe lanes off the PCH controller already. Likely what would happen is something currently on the CPU’s lanes would move to the PCH. This assumes the T2 and two TB3 chips are all on the CPU lanes already. Don’t worry about the lanes, IMO.
I've been of the opinion that the CPU lanes are reserved for Thunderbolt ports for best performance. This is why the Mac mini can have 4 Thunderbolt ports - all 16 lanes coming from the CPU.
Discrete graphics would hang off the CPU lanes too - usually 8 lanes - explaining why iMacs only have 2 Thunderbolt ports taking up the other 8 lanes.
Everything else is patched through the PCH chipset (USB ports, SSD, wifi, bluetooth, HDMI).
eGPU is a useful if limited solution for mobile users but also a pricey solution for Mac mini users. It's the only way to get some GPU upgrades even if, in some ways, it's better than putting it all into the same box given Apple's cooling solutions.
4K gaming is rough right now if you want to court more than the indie devs, even on something like the 5700XT. Something Mini-esque with HDMI out for hooking up to a TV, but with KB/M and external monitor support would fit better IMO. A gaming laptop seems like a bag of compromises and doesn’t offer much over the 16” MBP.
Meanwhile, done right, it could double as a gaming system you can hook up to a monitor or TV, but also a “Mini with more graphics Oopmh” if they want. They could play with refining the formula behind some of the smaller (sub 10L) ITX cases on the market. They could make something that takes a 2-slot desktop card but is also smaller than the Dan A4 if they really want.
Something about 'Mac gaming' doesn't hold up about that recent shaky story the more you think about it. Apple just aren't ready to be the best option for gamers going forward.
When they say eSports in the report I'm thinking multiplayer action titles that don't need the highest end hardware. Usually it's just powerful enough to run simpler titles like DOTA, Starcraft 2, Overwatch and Fortnite. It's eSports rigs that get talked about when people put their ITX sized gaming rig in a bag and go round a mate's house to play.
Most of the discourse around 'gaming Mac' has been around what I call a misinterpretation of what PC gamers call AAA titles - the games that need the very best Nvidia GPU and top of the range Intel gear - Call of Duty, Crysis, etc.
We all know that macOS as it stands doesn't get enough developer support and Metal isn't being utilised to the max. It doesn't help when Apple lose interest in developing technologies like OpenGL and consistently don't put top of the line graphics hardware into Macs (or even current hardware for that matter).
Its therefore no surprise when we read about PC titles getting more FPS when run in Windows on Bootcamp using the same hardware.
A Mac mini with internal GPU, better cooling system if Apple overlay chase the gaming angle, would be costly for sure. How many gamers with that much money would buy one? Over the hobbyists who wanted a Mini with more graphical grunt but balked at the price of a mini plus eGPU combo?
The more I think about it, the more it makes far more sense for Apple to produce a games console which is capable of playing the eSports titles being mentioned. The ARM CPUs should be capable of at least Xbox One X/PS4 Pro performance next year - maybe even give the Xbox Series X/PS5 a run for their money too.
Apple would certainly be able to push a portable gaming angle with the iPad/iPhone too.
The other thing I would be doing is acquiring a games studio to make exclusive titles for my games platform. With Catalyst it should not be too hard to code something that could run on both iOS and macOS.
In the meantime I would also be tapping up Mac friendly studios (eg Blizzard) to release certain titles for Mac and iOS - Overwatch for a start.
T2 doesn’t even have a heat sink and hardware decode/encode is very low power consumption compared to the rest of the SoC... I’m not sure what point you are even trying to make here.
Probably not worth fully forming the argument yet but I'm reading a number of threads about T2/BridgeOS issues suggesting that improperly cooling that chip can lead to issues and perhaps ultimately the death of the system since it's so pivotal for security reasons and if it were to die prematurely it would be very bad for a Mac.
Those threads aren't hard to find but it's certainly worth monitoring in case it's not a temporary software issue.
In these cases I'm guessing the total system heat is the issue and not anything the T2 is doing by itself. Interestingly, Appleinsider have an article about the assistance it gives to
video encoding and it's worth pointing out that the iMac Pro doesn't have Quicksync because the Xeon CPU they use doesn't have an iGPU. It's also fair to say that the new Mac Pro has the same issue but both of these Pro machines have the T2 CPU to take over from Quicksync.
Quicksync also helps with
AirPlay mirroring although macOS Catalina's
Sidecar feature does actually seem to work with iMac Pro and the new Mac Pro so I'm wondering if the T2 CPU is handling the grunt work that Quicksync would have handled if the Mac doesn't have that feature.
The point to be made here appears to be that the T2 CPU is taking over where the Mac doesn't have native quick sync - iMac Pro and new Mac Pro are the main examples here.
That could be taken as evidence of Apple reducing reliance on specific features of Intel CPUs. It does appear to remove reliance on iGPUs but AMD don't offer anything with an iGPU that Apple would be interested in. While this might not be an issue in the iMac (which does come with a dGPU) it will be an issue for the Mac mini specifically as that relies on the iGPU.
If, then, Apple have decided to introduce more GPU capability in future Macs because of a strategy shift to start catering more for gamers it makes sense for the Mini to have a dGPU on more affordable SKUs. These machines probably won't be of interest to the Colo guys because of the GPU.
On that basis, Apple could be free to design a larger case for the Mac mini Pro to include desktop CPU and add in discrete graphics if they continue to sell the existing Mac mini with perhaps a storage bump to keep it ticking over.