they are not at all... mine was great (Halifax County High, VA). It is rated 5.5/10, so average school I guess and it was diverse.
I attended it as an exchange student, (From Albania), from my senior year.
I took mostly AP classes, and they were pretty good, as the average student was very/well motivated. They were smart and most went to good colleges after it. I got the chance to advance many of my skills, computer wise, and even took programming, which was great as it cemented my desire to pursue CS. (Pascal was the language being taught in 99).
Things like AP physics and biology/chemistry were way behind my Albanian education. I can't image what Gen Ed physics would look like. (probably comparable to middle school level in former commie Europe). AP Calc, was challenging and on par with former communist country education (but very few people take those classes).
Gen. Ed classes, (the ones where average people take) were a mixed bag, as they had plenty of students that clearly didn't want to be there, and just wanted a pass grade and move on.
I also got to join the soccer team and I loved it. Made lots of friends, never got into a fight (perhaps because I was the only foreign student, and people were super friendly), went to the prom, and all that. Became friends with the popular/'in' group of girls, had a gf., etc... It was something like out of the movies.
For me it was a great experience, and it really really depends on how you use it. If you take mostly AP classes, or participate in sports, it is a great thing. If you take the gen. ed classes, you will end up in classes that are designed more to just teach the bare minimum, as most students there don't have any interest in being there to begin with.
The trend of reducing AP classes in the name of 'equity' is very troubling, as it remove the chances of smart students to have a stimulating environment, and let them learn at their faster pace.