What? You think it's not a real study, just because in your area it didn't/doesn't happen? You go on to use notebook paper for writing, as if you think you are making a point, but you are just making yourself look ignorant, as it's a common item that every school list has on it, as it's the core supply needed by every student across the nation since the beginning of time. well as long as school supply lists where a thing.
I guess you missed the 2 rems of copier paper (used by the school), red pens (forbidden for a student to use because that is what teachers use for correcting), 3 different types of plastic bags, expandable file (WTF is this for, other than the teacher/school to use for the student's file - folders are much, much cheaper if it is for student organization, but doubtful that is what it's for, most likely for the teacher's use, and they most likely pull it out during teacher conference to "show" the parents examples of their student's progress), Invisible tape refill (only purpose is for the classroom refillable tape dispenser - which refills was always school supplied). Clip board (HUH? The only people who used clip boards when I went to school are test givers, and P.E. teacher), Sharpie (only real purpose for this in school is for labeling shit, which such markers use to be school supplied), white board erasable markers, and eraser (both of those are teaching tools, primarily used by the teacher), card stock for kit building (from my understanding, used during art, was supplied by the school in my day), transparency markers (for teacher to use on overhead projectors), 6" protractor (re-usable year after year, was always school supplied, although they where crappy), yellow sticky notes (office supply needed by the student for school?).. over half of the list is supplies the Schools use to supply, which also included the art pencils and such, as most of those art supplies they require would last years before needing replaced in the 4th grade. . At least when I was in 4th grade 42 years ago, and when my first kid started school nearly 30 years age, my last kid, it was totally different, and it is when the lists started to grow year after year, some have even included staplers. As for forcing brands.. BULLSHIT! They want specific brands, they can supply them. They don't get to dictate what I spend out of my wallet via brand requirements, nor should they be allowed to do it for anyone else.
Point is, It never use to be a normal school supply list, and an example of what is happening in many schools across the nation. It doesn't mean it's not true because you have never experienced it. Now I looked up local school lists from this past year, and thy all shrunk substantially. Hmm.. wonder if it was COVID related as a lot of schools shut down, meaning they had all these school supplies they collected that where never used. And yes, they collect all the supplies now days in a lot of schools, and they go into a "community" closet for every one to use.. Something that has also changed. Use to be your supplies where your supplies..
The over all point was All forms of education, the cost is sky rocketing, it's not just Colleges.