Most likely he's been getting by with workarounds (not running everything simultaneously) and expected the new model to be more capable.
How has it come to this?
It's actually "more efficient resource utilization per instance". Perhaps, with increased capability comes increased utilization. While before one would run only one or two VMs and try to run all their apps within that, now one can run many containers.
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That, and shareable memory across host and guests.
But I guess that works only if the host and guest run the same kernel. Docker and vagrant on OS X still have to dedicate some RAM to the Linux VM running as docker host, and I don't know how efficient other facets of docker on OS X are; but on Linux, I find containerization's memory usage almost at par with running the apps directly on the host.
For me the issue comes down to lack of choice. Previously lack of choice from Apple was not a concern because the choices I would make were inline with what they are offering. This is no longer the case.
For those that asked, I am replacing 10 years of using MBP's with a System76 laptop. I don't have it yet so I can't comment but I am excited for the change as have been growing more and more frustrated with Apple.
You would also be able to forego the VMs since you can run your containers on the metal.
It's a highly configurable, professional machine.
http://shop.lenovo.com/gb/en/laptops/thinkpad/p-series/p70/
The Dell Precision M6800 (no longer available) supported a 4 drive configuration if one was a Mini Card plugged into a slot on the motherboard, It had three 2.5in drive bays. You could have a look at the current Dell models, or an HP Z Book.
I feel like I'm tired of being on a machine with a centralized system anyway. I want something basic with OSX images - an OS X just for work, and OS X just for finances, and OS X just for music work, etc. As it is I have multiple user accounts for different clients - I get some isolation that way but things still get in the way in a few ways. Strange IntelliJ bugs, occasional homebrew permission conflicts, etc. When I find myself considering buying multiple laptops to be free of all that, it's reached a ridiculous point.