Class size doesn’t always matter or mean better/worse education. Think of a large lecture hall filled by students who want to hear an excellent professor. Better than being in a small room with an average prof stating his/her views. Think of top notch TA’s- tomorrow’s professors leading discussions or some average professor who has been there forever. Think of being able to choose from several different professors in a department instead of having X for multiple classes. All sorts of ways to look at things/distort them. Consider the peer group, which is why some students choose small or large. Think of course availability- how many different freshman chemistry courses or foreign language/literature courses available. And of course, one’s proposed major counts- math at an LAC or with honors at top twenty math grad program flagship U taking grad courses (several) while an undergrad. Public schools are generally two-tired, serving the typical college student and the gifted ones whereas private schools tend to serve one group or the other. Could go on and on some more, but you get my point.
Fortunately there is not one-size-fits-all education in the US.