It's pretty common knowledge that there are differences from the GNU package set and linux package sets.
I've been exposed to this multiple times: from downloading GNU packages using Homebrew on OSX, downloading different packages on Android, the variety of options available to ArchLinux users, etc.
Anyone with basic Linux knowledge should be well aware of this. From a minimum of following tutorials and having the basic command flags not work on common terminal programs.
I don't agree that "basic Linux knowledge" requires knowing which commands have different versions. You can be intimately familiar with the Linux kernel and never step outside of the GNU environment.
I've never used OSX, and have no desire to compile things on my phone.
And I know that there are non-GNU versions of some tools, like grep, but whenever I've attempted to use them, I find them lacking some key feature that I always use. I can't be bothered to learn the entire set of GNU-improved tools, since I'm always just going to be using the GNU version anyway.
I've been exposed to this multiple times: from downloading GNU packages using Homebrew on OSX, downloading different packages on Android, the variety of options available to ArchLinux users, etc.
Anyone with basic Linux knowledge should be well aware of this. From a minimum of following tutorials and having the basic command flags not work on common terminal programs.