What you say there would seem hard to argue against. Probably we are slightly skewed on observing each others points of view.
However, I paid a lot of attention to what went on in school as my children grew up, and regardless of what anyone says, teachers or otherwise, there's no doubt in my mind that the parents who didn't seem to give a damn had the kids that did badly academically. I'm going to say here that the immigrant parents of the past, and likely the present, probably gave very much of a damn and likely pushed their kids pretty hard in many cases.
But I jumped into this conversation by stating that the problem with public schools is that they don't have much in the way of academic standards anymore, which is what I still think. Of course, also their adoption of political correctness as an MO.
I would add, vis a vis the discussion on homeschooling, that the same parents who participate actively in their childrens' education in public schools are the ones who'd make good homeschoolers - the ones who don't probably wouldn't or couldn't.
I tend to agree with Sam that the "give a damn" factor has decreased in recent years. I'd also suggest that the family structure was stronger at the turn of the century than it has been since the implementation of some of the "Great Society" programs and the "cultural revolution" of the 60s and 70s.
I've also read that in the early part of this century, some of the schools in the immigrant communities were taught in the native language, rather than in English, which I thought was interesting.
I do agree that students in poor schools need strong academics, and it seems that the most successful programs in those areas have a strong academic and a strong disciplinary component.