One could also argue that in an internet world the OS doesn't matter. But I would instead argue that in an emacs and bash world (which run everywhere) the OS doesn't matter. But that's just me.
I probably should have proof read my long rambling post and got rid of about 75% of it. You summarized what I was trying to say very effectively with much fewer words. If your goal is to accomplish something productive the operating system is almost irrelevant much of the time.
Various operating systems have personality traits which makes them distinct from the others. But to me they are still a lot like automobiles. Most of them are fairly dependable and in general get you where you want to go in approximately the same amount of time.
I really only notice when something I am used to using is changed in an irritating way. For example, I believe it was when Android went from Gingerbread to Ice Cream Sandwich the way external storage was used got mucked up. I understand the reasons why this happened but years later it still takes a work-around in many applications to keep them from using up your internal storage space. Even if you have your Android device rooted it is still fairly complicated to repartition your internal storage space, which would be an easy fix for many devices.
Last year I gave my dad a new Windows 8.1 laptop because his Windows XP laptop is starting to fall apart. I understand why Microsoft wanted to update the looks of Windows 8.1 but now when my elderly parents call for computer advice it is generally about something that was changed that was working fine to begin with. Before I gave the computer to him I made every effort to set it up so that it acted as much like his Windows XP laptop as possible. But there are still a few changes that were made that throw him off. He still ends up using his failing Windows XP laptop about half of the time because he is more comfortable with it.
So I did it again and started ranting about off topic stuff... sorry.