Is school and college football in Texas and other Southern States the best standard in the US? I don't know anything I'm from England but I love Friday night Lights!
It's a close call. Certainly the intensity of HS football is greater in the South-particularly Alabama and Florida. In some areas there's really nothing else going on besides HS and college football , in terms of sports/entertainment.
But the SEC also -even for college football- plays fast and loose with regulations. Over the past 2-3 decades there's also been a population shift to the South which gives teams a larger pool to recruit from.