/{bin,sbin} is for stuff you cannot live without (e.g., sh, mkdir, chmod, rm, ln, etc.) /usr/{bin,sbin} is for stuff you can live without but expect to be ther

/{bin,sbin} is for stuff you cannot live without (e.g., sh, mkdir, chmod, rm, ln, etc.) /usr/{bin,sbin} is for stuff you can live without but expect to be there (e.g., make, grep, less). /usr/local/{bin,sbin} is for stuff you/your local admin installed (e.g., mosh, cmake). Also, I use $HOME/{bin,sbin} for wrapper scripts, binaries that I need but don't want to install system-wide (single-file C utils that come without man pages, stuff like that). I'm not sure where the confusion comes from and I don't really see any advantage in merging / and /usr. On the flip side, I do think there's value in keeping /{bin,sbin} as small as possible (because that stuff has to work).