Actually, why people are walking away from BP (traditional ) muzzleloaders is due to several reasons. And trust me, just about every time I go to the range here I try to help younger folks understand traditional ML's. Many younger folks walk up to me and enquire about mine, so I explain things to them. They all seem interested but I would wager not the first one went any further with their interest. IMO, it has little to nothing to due with folks not helping.
These are the actual reasons that I see why folks are more interested in MM than us folks that prefer the old side lock, traditional ML's.
1. There is hardly any sporting goods stores that carries traditional ML's, if any at all. They get no exposure in the general public. Therefore, traditional ML have, in essence, become a thing of the past.
2. Even if there were sporting goods stores that carried traditional ML's, folks want any equipment that gives them an advantage while hunting. A scope is highly thought of for poor light condition hunting conditions. Some MM have screw in breach plugs, which is another advantage to some folks. Primers that are are covered and not really exposed to moisture, etc.
3. Black powder is difficult to find in any sporting goods stores. So folks have gotten use to using alternative substitute propellants.
4. Limited shooting accessories at sporting goods stores, such as conical, patches, RB, caps, etc.
5. MM are basically the only type being promoted by magazines, TV adds, internet, TV hunting shows, etc.
6. Many folks want the easy way out for just about everything and anything nowadays. They don't want to take the time to learn how to clean and shoot traditional ML, or with learning the proper patch, ball, powder combination. And they especially do not want to fool around with messy BP that is difficult to come by, other than internet order and having to pay Haz Mat fees.
7. And the main reason, IMO, is because MM gives them an advantage on a big buck or elk. The effective ranges are extended along with better longer range accuracy. Composite stocks and stainless barrels are better for foul weather hunting, a built in safety, slings and/or sling studs, and on some MM a scope, all right out of the box.
I vow to keep my traditional ML's and hunt with them for as long as I am able, but the cold hard facts are, they are much like the steam engine, they are quickly becoming a thing of the past. Technology sells, whether we like it or not.