Arch is something a fairly non DIY user can easily conquer and use for many years and it will just work. As long as they don't choose to do anything exotic, they can use it basically forever.
NixOS is nothing like that, there's limited docs, the docs are sometimes just RTFM that links to another RTFM and oh yeah don't be afraid of breaking userspace because userspace is doing something wrong. It's fine for some of us who can of course get shit done.
Ultimately, I think some subset of Arch users who really wanted to be Gentoo users but weren't because "drama" and then NixOS scratches that itch.
Basically it's all about Calories and Americans have added 25% to their caloric intake since 1961 when it started increasing.
Its also not really magical, they didn't just add sugar, they added meat, sugar, grains and oil (replacing butter mostly) - all together it adds up to 720 kcal extra per day per capita.
Koreans eat about 1500 kcal less per day (they are also quite a bit smaller on average so it's not 1 ot 1 of course.) Japanese eat even less (like 200 kcal less) but are also even a bit smaller on average. Both countries happily eat terrible food just as much as Americans do these days, they just eat a lot less food in total.
There's an idea that American eat out more and that the calories at dining establishments about increased about 35%.
The C++ coding style is also very much the way a Windows developer would write C++ code. Not the way a Unix-y C++ developer writing on Windows would write.
I always figured based on the code and the emails that it was an older Japanese developer. I've emailed 100s of them over the years and they do all typically write similar in English, they mix a lot of UK/US-ism, and often their English is really good, like I wouldn't know they weren't a native English-speaker until I just caught on to how they wrote. (Speaking is an entirely different issue, many of them cannot speak English in person very well or make obvious grammatical mistakes they don't make when typing.)
She was able to detect a person who they thought was a false positive and turned out several months later did have Parkinson's. She detected her husbands before he had signs as well.
They also found the molecule she was smelling which was expressed with sebum. This isn't entirely unfounded as they already knew about dogs smelling cancers and other various diseases.
NixOS is nothing like that, there's limited docs, the docs are sometimes just RTFM that links to another RTFM and oh yeah don't be afraid of breaking userspace because userspace is doing something wrong. It's fine for some of us who can of course get shit done.
Ultimately, I think some subset of Arch users who really wanted to be Gentoo users but weren't because "drama" and then NixOS scratches that itch.