The technical details are all right (or seem right to me, anyway), but this is too opinionated for my liking. No, you do not need a 4K monitor for software development. Some people might like them, some won't. [edit/clarification: someone rightfully pointed out that nobody will actively dislike a 4K monitor. I was unclear here: I meant "some people won't need them" more than "dislike them"] This sounds like when Jeff…
I was one of the people who worked on 15” retina MBP everywhere, even in the office where I had 30” on my desk, to not have to readjust and keep optimal habits for the screen size. Now I simply refuse to work on a laptop at all, it feels like being trapped into a tiny box and I get literally claustrophobic :)