Where is the point that it becomes unreasonable? Why 24? How about 20? Or 23, for that matter. Or 50 Something like that young woman featured in the news? Some schools place limits. How firmly they will stick to those limits if there is pushback from parents, I don’t know.
My youngest applied to 8 colleges early. He was done in December, he told me once he got his first EA acceptance. If his EDschool accepted him, he was pre-committed. But it did not, he was going to go that EA school. He was fine with his applications.
He had had a list of RD schools he was going work on, if he did not get into the ED school and it had 24 or so schools on it. Not that he’d apply to all of the schools on that list. The composition of the working list would depend on which schools accepted him in the early cycle. As it turned out, the list ended up empty.
But early in the app process, he wanted to apply to a half dozen or so highly selective schools just as lottery tickets. Then a group of schools also very selective. Then a group of likely/match schools that he really liked that did not have Early Action or rolling admissions.
My other son had SAT scores in the lower quartile of the schools he liked. But his grades and course rigor were high. We cut a wide swath getting a list together. He liked the larger state schools that I felt very unlikely to take him because of their formula admissions. But he had about a half dozen on his list along with Fair test schools and Catholic schools and a few long shots. It can add up fast