Not unsolicited, and only up to a point - 1) I don't have kids but I HAVE been a teenager and if somebody asked me about their teen I would have some thoughts about what they should do if they don't want to end up with adult offspring who don't speak to them ... and 2) I mean I may well be living in the same town when the little gremlin is 20 years old, 6-3 and 240 and mad at the world, so in broader society terms yeah I think there's some validity to comment on how kids are being raised no matter who you are...but in the day to day, moment to moment real world, people are for the most part doing the best they can with whatever resources and mechanisms they have available and being mad about babies crying on airplanes or whatever is on the mommy blogs and shit like that almost seems...mean-spirited?

Some parents, many actually, are truly awful people and put their children through hell and leave them with lasting psychological issues. There's no excuse. Though I understand that there are many things parents do that non-parents judge them for just because they don't understand how difficult and taxing children can be, things that they'd probably do themselves eventually if they had children. It's not ideal but I guess it's understandable.
I don't give advice because I'm too shy and also I know that parents hate getting advice on parenting from non-parents. Even if I think the children are unnecessarily suffering and/or are being conditioned in the worst way, I don't give advice. I'm not sure if that's the best thing to do or if I'm just a coward.
Also all parents deserve judgment for bringing more people into this God-forsaken world of suffering. But I usually don't think about that just because someone has kids, it takes special circumstances for that to annoy me.