We don't micromanage their online access, but we do try to encourage being online in healthy ways:

We did no smartphones before high school. (Have had zero problems with that in terms of their social acceptance) Also, no computers in their rooms - everything is done in more shared space, with monitors facing the rest of the room. We talk about what kinds of content to watch out for, how to think critically about it, and what kinds of content or people are more serious, that they need to let us know if they run into. (Stalkers, scammers, other such actively harmful stuff.)

That does give them enough freedom once they hit high school to be more secretive about what they do. But we feel that is also more appropriate as they grow older. There have been problems. When they occur, we talk openly about them and help them both resolve the problems and learn from them. We are big believers that wisdom comes from experience, and experience comes from doing, so we try to focus on letting them expand their autonomy as they grow up, while at the same time minimizing harm when mistakes are made and learning from them.