In Washington state, when they first instituted ML season, it was in addition to modern rifle, or "regular" rifle season, and you could buy a tag for both. So an awful lot of guys were buying two tags per season. I would guess the Game dept. made a lot of extra bucks. I used to think ML season was created for us Danial Boone types, but now I'm seeing a monetary motive. ?
After a few years it became either/or, one tag only and you had to choose between modern rifle and ML. However, ML season allowed "any deer", you could shoot a doe. That eventually morphed into the same buck-only requirements of of modern season. The only thing ML has now is a few late season limited "any Elk" areas, which are few. Lucky for me one is two miles from my house. Unlucky for me, all the Elk here move over to the wildlife refuge as soon as hunting season opens. We have a lot of Elk here, but catching one on state land, when the refuge is only six miles away, is really difficult.
This year's late ML deer season was buck-only, and near home here it was buck only, 3-point minimum. !!
So now I don't see where the state makes any money off of ML tags. Perhaps that is why they have no interest in keeping the season "traditional", if they ever did. I think that if they changed the requirements to strictly traditional now, they would lose 75% of the ML tags they sell. At least.
The only real advantage now is that ML season comes before rifle season, you get to hunt before the regular season and the game becomes really spooked. You would think there would only be the Daniel Boone types out, but as I'm mentioned before, I rarely see other hunters out with traditional muzzle loaders. If the motivation is not tradition, or selling more tags, I'm kind of surprised we have any ML season at all. And since the Wolves are decimating the deer and elk, here and in Idaho, I'm not seeing where much game management is taking place through hunting. ?
I still think the choice between modern and traditional ML's is mostly a matter of taste, and whether one is into tradition and history, or not. And who one associates with, will steer a new hunter one way or the other, and of course all the other reasons stated.