Pretty please!
vi is a text editor, not a system recovery tool. If you want a basic system recovery tool, there's ed in /bin. User applications belong in /usr/bin.
I don't wish to learn ed specifically for recovering a system as vi is what I am used to. When my system is borked I really don't want to have to use a tool I'm not used to in order to recover it. In order to recover a system you often need to edit files, you should use a text editor to do that.
*shrug* then use a livecd. You could just as easily say "sometimes I need a compiler to fix my system, so gcc should be in /bin", or "my favourite editor is emacs, so it should go in /bin".