L-J,
I think you have your eyes too far up your own domain!
I don't think that LTA was ever going to replace fast jet freighters who's business is getting some stuff from a VERY long runway to another VERY long runway, very fast. You're comparing a Articulated Lorry to a Canal Boat.
Try this...
What about getting a lot of stuff to an isolated area 'fairly quickly'?
Replacing trains, trucks and boats instead of planes? - And possibly without the use of a long runway or a Station/Siding/Ramp or even a deep enough Port. How about just using a big flat piece of ground, like a farmers field(s), without any paving on it?...or possibly low lying water?
How many of your big jets could attempt that?
And as for the 'blowing them out of the sky' What would a missile hit? What would it burn? What percentage of Lifting Gas would be lost?...if it hit a Lifting Bag.
Even if it hit an engine...so what? it has another three widely spread apart. It's to have diesel engines so that too is no more dangerous than for an conventional airframe.
Get your brain into alternatives not negatives.