No decline, just people doing things differently.
Not buying in person or supporting local businesses.
Branching out into new technologies.
Seeing engineering skills as secondary to other hobbies (that are now much more advanced/ambitious than they used to be) rather than an end in themselves.
Hardly anyone understanding that the 'maker movement' is exactly what model engineering was 100 years ago before it got typecast as locos, traction engines and clocks.
I bet there are more lathes in private hands now than ever before and vastly more mills, but with the internet a large proportion of these people are self sufficient, and don't join clubs, visit exhibitions and only find a forum like this or a magazine like ME/MEW by accident.
There is a huge appetite for engineering related hobbies, check out Instructables, Thingiverse and Men in Sheds. All ages, all skill levels, they just don't relate what they are doing to model engineering unless we get out and tell them.
Neil
Edit – I'm reminded of the book about recent social change in America – Bowling Alone. The title says it all.
Edited By Neil Wyatt on 17/08/2018 00:30:24