I don't think people will have many complaints about this thing, but I do think this will be one of the primary (even though it's basically a non-complaint).
It will definitely be used to justify spending $300-1500 more for a better laptop.
The same things Macbook pro users plug in where they'd see the USB speed differences. Just because someone isn't as privileged as to be able to afford a MacBook Pro instead of a Neo doesn't mean they don't have the same dreams and desires.
For monitors at least, if you plug in to the wrong port you will get a GUI prompt advising you to use the other one [1]:
> while the ports aren’t labeled, if you plug an external display into the “wrong” port, you’ll get an on-screen notification suggesting you plug it into the other port.
I hope they added (or will add) that feature to other Macs too, on mine I had to try out different ports and check the settings to find the one which can go beyond 60Hz.
It will definitely be used to justify spending $300-1500 more for a better laptop.