Agreed. Some of those hardened bunkers can take a direct hit from a reasonable sized nuke (say 250 kilotons - that's 250,000 tons).
I would have expected either a whole lot more HE - say 200 tons or so, all 2000lb guided munitions - or fewer really big bunker busters.
People talk about MOAB, but that's not a penetrator, it's for troops in the open.
they could die from repercutions too... not necessarily blowing up the bunker but enough boom to shatter internal organs and such