It will help you meat friends and get into a clan, that clan/friends will help with hard
Possibly, they realized that that'd be a much bigger issue. Heroic Raids tend to require good team coordination and familiarity with the raid itself. Guided mode for Heroic would cause a lot of friction, arrogant players thinking they can do it, etc. Better to allow guided for normal mode, allow rookies to find teams, get experience, etc.