Changed for the worst? Really? I think you're way off the mark. There's always idiots passing through this game, nothing can be done about that. But I'm pretty sure there was one or two undercover documentaries in the 80s that didn't bode too well for our sport? The world is a much smaller place now and it's a lot easier to figure out the clowns, plus there's plenty of books and information around now that helps young terrier owners in the basic principles of terrierwork, one dog at a time etc.
What was available in the 80s? Plummer and his bullshit.