So, do you think that when the Mac Studio gets upgraded, it will also come with less max RAM, but be unified?
Is the whole "unified" RAM a reason that the iMac and Mini are capped at 32G?
Is the whole "unified" RAM a reason that the iMac and Mini are capped at 32G?
Unified memory is much more useful when you can get more bandwidth to it.
GPU cores are generally identical between the iGPUs and the discrete GPUs. Adding a PCIe bus (high latency and low bandwidth) and having a separate memory pool doesn't create new opportunities for optimization.
On the other hand having unified memory creates optimization opportunities, but even just making memcpy a noop can be useful as well.
The performance dependency on DGPUs doesn't come from the existance of a PCIe bus and partitioned memory, but from the fact that the software running on the DGPU is written for a system with high bandwidth memory like GDDR6X or HBM. It creates opportunities for optimization the same way as hardware properties and machine balances tend to, the software gets written, benchmarked and optimized against hardware with certain kinds of performance properties and constraints (like here compute/bandwidth balance and memory capacity, and whether CPU & GPU have shared memory).