i think the problem with big backpacks is that they can be unsightly but if you have a large backpack that looks cool then what's the problem? as someone who commuted to school all four years (except for the covid ones) that backpack is literally your apartment on campus; it's great to keep it light for an average day but if you ever need to pack more stuff into it a little backpack won't let you do that
also don't let memes about freshmen discourage you; they're proliferated by people who were in the grand scheme literally just freshmen themselves. not even joking mere months after graduating all undergrads were unbearably annoying to me and indistinguishable from each other
linked is my daily driver backpack c. 09/2021 i will literally never get rid of this bag and it's pretty huge