From the article: Despite Apple Silicon currently working solely with its own on-board GPU cores, Apple is researching how to support more options, like PCI-E GPUs, all working in tandem.
One thing Intel Macs had that Apple Silicon ones do not, is the ability to use GPUs in external enclosures across Thunderbolt, or internally in a Mac Pro. There are just no provisions with Apple Silicon to do so, at present.
It might not be an issue that concerns most Mac users. It is a big deal for some — and particularly for Mac Pro buyers.
Now, however, a series of four newly-revealed patent applications appear to show that Apple is at least considering this issue.
Apple Silicon brought dramatic, practically unheard of, performance and capability improvements over the earlier Intel processors. Part of that was how the new Apple-designed processors cut down on previous bottlenecks.
For instance, unlike typical RAM chips in a device, the new Unified Memory system saw the RAM installed on the central processor. It means you can’t upgrade it later, but it also radically sped up how fast that CPU could use RAM.