Sure, but the threshold between "Retina" vs Non-"Retina" is somewhat arbitrarily decided by Apple, and it's also a registered trademark that only Apple owns.
It's like arguing whether or not macbooks are "ultrabooks". Choosing to discuss using these terms is ultimately just allowing these companies to arbitrarily control discussions. I think we should try to resist corporate capture of language when possible.
Consider the context of the parent comment. If I can barely notice individual pixels on my 1080p monitor with good vision at a normal viewing distance, then surely the difference between a 4K screen and a 2K screen can't be that noticeable, even to a professional artist (who probably has more ideal viewing conditions, a more trained eye, and lower viewing distance).
Looking at apple's website, their MacBook Air (which I assume is their main model?) has a "retina" resolution of 2560x1600 with a 13.3' display, whereas the framework has a resolution of 2256x1504 with a 13.5' display. So they are about the same, except that one is marketed as "Retina" and one is not.