It's been years since I've been around ACHA hockey, but my experience matches yours. In the 90s, you were happy to get kids who at least played on a high school team. Believe it or not, playing high school hockey was a much lower bar than it is now. By the early 2010s, those same kids were getting cut.
And around the same time (1990s), I do remember ECHL games were nothing but fights. Were they called the Wheeling Thunderbirds at first?? Now it's a legit AA option and even some of the single A leagues are sort of legit these days. I think it started when NHL teams needed a place to put their goalie prospects and it kind of ballooned from there. I'm not sure that the money is a whole lot better for the average ECHLer, but they do offer housing and some other amenities now.