Amazon EC2 M4 and M4 Pro Mac Instances

I'm so so so interested to know how AWS Nitro interfaces with these systems, provides control and fabric. All I can guess is that it's an external thunderbolt based implementation?

There's some kind of photo in this m2 blog post, but not super clear. https://aws.amazon.com/blogs/aws/new-amazon-ec2-m2-pro-mac-i...

I wonder, if rack mount Mac Pros weren't so stupidly expensive, would AWS go with those instead? (assuming they wouldn't be able to get a good offer on those). I can't imagine it was all too pleasant to have to develop these rack mounting solutions for these minis (unless they used a preexisting one). Although if they can fit multiple of those minis in the space one Mac Pro would've took, it could be more efficient and therefore worth it?

All of this is ignoring the fact that current M2 Ultra Mac Pro is just barely better than M4 Pro mini (unless thermals are an issue on those, haven't delved into the reviews and/or benchmarks)