You might want to consider individual levels of tolerance for dpi's as an explanation for upsizing the screen. For example, my tolerance for small text at 1:1

You might want to consider individual levels of tolerance for dpi's as an explanation for upsizing the screen. For example, my tolerance for small text at 1:1 is about 160 dpi (4K on a 27" monitor), which is much lower than the 220 dpi of your Retina 15. Having said that, my eyes would have a better chance of tolerating the same 2880x1800 resolution on a 17" monitor at 200dpi. At some point, that extra resolution is going to get wasted on a small screen if you're more interested in real estate over crispy retina text. I have a 4K 15.6" laptop, and there's no way in hell I could tolerate it at 1:1 with my aging eyes.