I really don’t think this is true. I think it’s much more a reflection on the offerings at any given high school that actually offers AP classes. (Many don’t.)
When we attended the engineering session of Bama Bound in 2014, the presentation started off with the professional leading the session calling up four current engineering upperclassmen, who represented a range of students in the CoE. One student (from AL if I recall correctly) came in KNOWING he hadn’t been adequately prepared in HS to start off in Calc I (where most freshman engineers begin their math studies). So he went the remedial route and retook some classes and then proceeded to go through the engineering curriculum with no issues. (I’m not sure if he took summer classes or what.) Another student had taken Algebra 2/Trig in HS and started in Calc. The other I think had taken AP calc and had done well but decided to retake the class to make sure he had a solid foundation for his engineering classes. There was also a student who began at Calc 3 and never looked back, but he was considered the exception to the rule. It was HEAVILY emphasized that you better not go that route unless you are quite sure you are an EXCEPTIONAL math student (students like @Beaudreau’s older sons, I presume).
The CoE strongly recommends all students start in Calc 1, but they’re not going to prevent you from using your AP credits if you want to.
In our case, there was no big decision to make because my son’s private HS did away with AP classes years before, so while my son had taken two years of advanced calculus in high school, he didn’t go through AP curriculum and refused to self-study for the AP exams, so he had to retake both classes at UA. He did very well in both, but mainly because he already knew how to self-teach and could handle the pace of the honors versions of the class. He watched a lot of kids flame out, even those who’d done well on AP tests, and saw others go through the curriculum with no issues whatsoever. And he knows others who did go straight to Calc 3 and did fine. (I think Calc 2 is actually the class that trips a lot of kids up for some reason.)
He also had to take English 103 (the combined English 101 & 102 writing seminar for students with high stats who didn’t AP out). He really enjoyed it, but it was MUCH easier than his HS English classes, even though I know many good students struggle with that seminar. Again, it comes down to previous preparation as much as how “smart” your student is.
I do think some students, especially the Type A kind who are extremely ambitious and want to try to get a master’s degree in four years and participate in all kinds of special programs, sometimes bite off more than they can chew, but any time you have so many students coming into a program from such diverse backgrounds, it’s not gong to be clear where your student falls on the spectrum. There’s no right answer for everyone.
My son will likely graduate with “only” a B.S. in engineering. He just didn’t have the credits in place to allow for him to get the M.S. in four years. Slow and steady is his approach, and so far it’s been a good one. He’s done very well academically and also had a good time at school. Anything else at this point is icing on the cake.