I know I have bias because I do this for a living but a few things to consider:
1- The Russians have exited. The Rubel is down 20%+ vs the US$. There are a huge # of Russian collectors so demand has been affected. There is demand being pent up and when the geopolitical thing settles down they will be back with a vengeance.
2-The US$ is also up significantly against all other major currencies, AU$, CAN$. EURO. This too has delayed purchases.
3- Lets face it, show attendance is down, not just in militaria but coins, stamps. Bennie babies etc. The hobby is now on-line that's where the action is. Major shows are now mostly dealer swaps.
4- No new young collectors, well you are right most young people do not have the $ to get into this. IMHO as people age history becomes more important to them and that draws people in... as well as later in life they start to have some disposable funds to even consider such a purchase.