The problem, IMO, is not that the kid who applies to 57 colleges is hurting other applicants. It’s that kids are wasting huge amounts of time and effort churning out applications that that are needless.
GCs, consultants, as well as dumb “journalists” who write about the students who apply to 1,670 colleges and get $7,520,000 in aid, should not advocate for students to apply to as many as possible.
There shouldn’t be any “hard” limit, like, say, 25, but the people who provide guidance and advice to explain that there are definitely diminishing returns beyond a certain number. That number does differ, based on a student’s profile, how those colleges are distributed among safeties/targets/reaches, how much aid a student needs, etc.
Personally, I think that 20-25 is a decent soft limit. So, as a kid approaches those numbers, they should stop and consider what benefits they have in applying to that many or more.
I do like the idea of some version of @socaldad2002’s idea of requiring that an applicant at least have some basic knowledge of a college before applying. That will limit the number of, I guess that I will call them “frivolous applications”. Things like “I want to attend an Ivy because Ivies are ‘prestigious’, so I will apply to every single Ivy League university”, or automatically applying to the top 20 colleges on some “best colleges” list. However, I do not consider mass application to the public universities of one’s own state to be in that category.
BTW, I would also prohibit universities from “targeting” students with mass mailings, especially low acceptance colleges “targeting” students who have almost no chance of acceptance. If colleges want to target specific populations of students, they should send out representatives to their high schools. I have seen a number of people posting here how they were “invited” to apply to some low acceptance colleges, when all that happened was that they received a mass mailed card. Looking at the colleges mailings my kid got, I felt that some colleges were purposefully creating that illusion.
Similarly to mass applications, I an OK with public colleges mass mailing students of their own state.