The problem is, there's no universal standard for what these keys should do. For example, many players conceivably have Fire bound to Mouse1. But with the Weapon State keys, one modmaker might use a bind for "secondary reload", while another uses that bind for "buy items" and a different bind for "secondary reload", leading to player confusion. Also, if a bind for one mod goes unused in another, it's likely the player will see ugly error messages for missing scripts or whatever if they accidentally hit that key. This is particularly noticeable with mods like Hideous Destructor or D4D, where it's practically a requirement to have a separate INI config for just that mod. That raises the issue of other settings a player has to manually sync across config files if they want to have a consistent experience (like resolution, map colors, etc). If you don't keep a separate INI, then you have to rebind your keys every time you play something new.
IMO, a reasonable solution would be to break out the "Weapon State x" binds in the INI to be mod-specific (like custom CVARs), rather than universally bound. They could still appear in the same space in the menu, but having them tracked separately would be a godsend.
