My views, but remember, I'm not a powerlifter. . .
Powerlifting is catching on as a sport because of several reasons.
The biggest reasons are it's acceptance level at the meets. It is one sport where a new guy squatting 300 lbs is applauded almost as much as the veterans squatting 600 lbs. There is a sense of belonging when you enter the sport. Compare that to other sports where you have to ride the bench or get cut from the team because you don't have the experience to start.
It is pushed heavily on public forums. Think about the routines that are suggested to new lifters, heavy on basic compound lifts. And not just any compounds lifts, but they have to be the bench, squat, and deadlift. Ask for form advice and you will get standards based in powerlifting because that's how you increase your numbers. Finally, how many times have we read, "Your lifts don't count until they've been performed for a judge."
In the public eye, gear is looked at the same way steroids are; it's cheating. So it seems pretty natural that raw events are becoming more popular. Also, gear is something that more experienced lifters get into, so it stands to reason that raw events are becoming more popular since the growth is coming from new competitors.