AP is just one of many advanced programs. There’s IB, A-levels (and other international ones im not as familiar with), dual enrollment, dual credit, etc. Schools can choose what curriculum they want to provide. My high school was a STEM magnet school and, while we offered a lot of APs, our advanced courses included differential equations, complex analysis, DNA analysis, organic chemistry, etc. None of these classes are APs, but are far more difficult and above AP classes (considered post-AP). AP is not a measure of how good a school. You have to look at what advanced or college-level options they offer.