As far as age demographics I believe the hobby is much healthier in Europe and Japan. This is how MIG, AK, Takom, Meng can make their margins.
I'm 58, and I don't know a single millenial that models outside of the occasional kid that goes to MIT.
You have 3 years olds that have iPads, that have to make a "date" to play. It's a differnet world.
You want to talk about a hobby in trouble, try stamp collecting. I'm considered one of the babies at 58. No one is coming to replenish when the old guard die off. Most of my friends in that hobby are well into their 80's, if not 90's.