I'm sure my experience was an exception to the rule, but when I went in August, there were 5 people there on a Thursday night (to be fair, a hurricane was coming in 2 days, and all of PI was hurting).
My thing with PI might come across as greedy and selfish, since I don't have kids, but it's supposed to be a place for adults. One of the few places that's not completely family-friendly. And if they're going to keep the streets open to everyone, it's going to get more mall-like. I said it once before, but it's only a matter of time before a teenage girl in PI with her family, but temporarily separated from them, gets abducted or slipped a roofie by some guy who's going to take advantage of her. OR some patrons are going to get drunk and angry, start a fight, and some kid's going to get in the way. As it is, I'm sure a lot of locals who are adults, looking to party, stopped going to PI because it's hard to get your swerve on when a family of 4 from Idaho are asking you to move so they can take a picture of their 8 year old daughter busting a move on the dance floor.
I thought PI was originally created because too many guests were sneaking off to Church Street for adult-oriented fun at night, and Disney thought giving guests on-site club action (with the requisite expensive drinks) would keep them around. I can understand a need, or desire, for more family-oriented action, which I thought was one of the reasons why DisneyQuest was invented.
IMHO, Disney made a huge mistake opening up PI for anyone and everyone to walk around. I'm sorry that some families might have kidw who'll whine that they want to go. I'm sorry that some families might have to spring for a babysitter so the grownups can go. But there are lots of places at Disney for the entire family to enjoy, and there are lots of places all over this whole wide world kids are NOT allowed to go into. I find it hard to believe that opening up PI to everyone generates enough income to compensate for the people that now DON'T go to PI.
If there really are people who insist that their kids chould get into PI, then make one or two nights a week family-friendly and keep it closed off the rest of the week for adults.