<<<Probably down to the owners leaving this world and no one taking on ownership, that and the expertise needed to keep them going slowly dying away.>>>

I imagine that has some effect.
However, a pal who has for 20 years done the motorbike equivalent 'Pioneer Run' tells me that it has always been quickly over-subscribed until the past couple of years.

Re TUD's post a neighbour was working for the railways replacing the clockwork station clocks and taking them to a warehouse (all except about 20 which he brought home and later sold).
Incidentally, he bragged that when he retired after 35 years he had never done a proper day's work.