[ChuckNorris89]

All Macs already have an ARM chip inside them in the form of the T2 chip.

[jedieaston]

But that’s specifically for Secure Enclave work (disk encryption, biometric data). I don’t think they’d want to risk someone running arbitrary code there and breaking the sandbox. (The SEP is also separate from the A-series chip in the iPhone for a similar reason, IIRC).

[monocasa]

In addition to the secure enclave, they already have an A series core on there. That's what runs the touch bar.

There's a full XNU based OS on there called "BridgeOS" that's in the iOS/tvOS/watchOS family.

[jdub]

Open System Information → USB on a Mac with a T2 chip and check out all the stuff attached to it.

[mappu]

So do all AMD Ryzen CPUs in the form of TrustZone/PSP, usually a Cortex-A5. It's equally as user-inaccessible as the T2.

[seedless-sensat]

There are probably a dozen ARM chips, e.g. WiFi module, battery controller, touch bar, etc