A sound reason not to take AP Computer Science in favor of say AP Calculus is that fewer universities give credit for AP CS, as one finds at the AP Credit Policy Search
https://apstudent.collegeboard.org/creditandplacement/search-credit-policies . Having looked at the introductory CS courses at a few schools (Harvard, Stanford, Princeton, MIT, U of Washington) I see that the introductory CS course is not standardized across institutions in the way that calculus is. AP CS uses Java, which is a common choice in introductory college CS classes, including at Princeton, but there are courses using C (Harvard), JavaScript (Stanford), and Python (MIT). The choice of language will affect what is taught, although all courses will talk about loops, conditional statements, and functions. One reason high schools may not teach computer science and programming is that there is less consensus than for math or science about what to teach.
AP Computer Science curriculum in changing next year. I am not sure of the details and how it will changed. But I wonder how this change will affect things. There is a problem that the AP system changes with less frequently than programs at a typical CS at university. At one point my local university changed their first language to Java at the request of local industry leaders, but since then it's changed to Python. I think a first class it's more important that students understand how programing works and beginning language is less important.
But AP Computer Science is not the only AP that isn't really useful once you hit college. My H.S. only offers non calculus based AP Physics. If you need to take Physics with Calculus for your college major, Physics must be retaken. AP Stats is also without Calculus, and if you are going into certain majors you have to retake Stats with Calculus. This is not necessary a bad thing but students and parent needs to understand those AP Classes aren't going to shorten the length of time to get the BA.
AP Computer Science is a popular class in my H.S. Yes it is probably 3/4 white or asian boys. Part of the problem with taking it is having the space to take it in the schedule. My son would love to take it next year, he has all the per-requisites but there is no room in his schedule. The most likely is he will take it senior year because our school has no math more advanced than Calculus.
I think it's much more likely that qualified teachers for the AP Computer Science are harder to find. While my son's school has taught AP Computer Science for years, non of the other schools in the district have for lack of teacher. A new teacher was just hired by one of those schools. People who can teach these classes typically don't have teaching credentials because they can make more money in industry or at community college level.
