> Be customisable
Valid reason. But he perfectly knew he was getting a proprietary OS, not Arch.
> because if you follow the Unix philosophy, each component is modular and replaceable
Who told him OS X follows the Unix philosophy? Also I don't understand the obsession with applying the Unix philosophy to everything. Give me a good full-featured browser and email program, keep your Surf (http://surf.suckless.org) and mutt if you want.
> Make it easy to compile, test and run any kind of software I'd like
Yes, like you can do already on OS X since forever. Obviously if you're going to do Linux kernel development OS X is not ideal and I think everybody can agree on that one. But for UNIX/POSIX software it's pretty much the same. You can get GCC from MacPorts and I guess Homebrew too, pretty much any version you want, if you don't like Clang (which is the default compiler in FreeBSD too btw).
> Be transparent in its workings, be easy to understand in principle
100% agreed on this one.
> Should be a separate entity. It should not rely on some third-party service in order to function properly. If I can't access the internet (or choose to airgap the machine eternally), it should be possible to run all of the software I'd like (and to use all of the features I'd like to) without needing access to online services.
I really don't understand this one. This is OS X, not Chrome OS. You don't need an Apple ID to update the OS itself. You can get programs from the internet or your favorite package manager without ever logging in with your Apple ID on the App Store.
> A package manager is useless if it doesn't manage all of the packages on a system
I wouldn't call it "useless", but I guess if you prefer a package manager for everything then MacPorts/Homebrew are not for you.
He then mentions that OS X has a "horrible development environment" without giving any actual reason, and mentions too "filesystem pollution" because OS X separates most GUI tools from the BSD tools (so he considers a logical separation between the BSD subsystem and the rest of the system "pollution". I think it's the opposite).
The post is a series of exaggerations and inaccuracies mixed with actually valid criticism.