Three things it actually does

First, it gives you a model of a domain — how a field thinks, what counts as evidence in it, what its characteristic mistakes are. That survives long after the particular content has gone. Second, it trains transferable capacities under supervision: reading hard things, writing clearly, arguing from evidence, judging whether a number is plausible.

Third, and least discussed, it changes what you are able to notice. Somebody who has studied statistics reads a news story differently. Somebody who has studied history hears a political claim differently. That is not a job skill, and it is most of what an education actually is.