i still tend to believe that the only lesson kids learn from content filters is how to bypass the content filter. electronic s̶u̶r̶v̶e̶i̶l̶l̶a̶n̶c̶e̶ ̶ supervision seems like it will yield a similar result. kids are going to see and experience the things you don't think they are prepared for and my personal anecdata suggests that they will survive. you cannot force them to be safe but you can be the one place they can always turn to when they do wish to seek safety.