Who is this "we" you speak of? The professional mathematician community? Were pre-AI results useful outside of this community of people who could understand them?

Yes. Most probably do not understand the notation involved in, and the statement of, the Lindeberg-Levy Central Limit Theorem. But every scientist uses this theorem in one way or another. These ideas have a way of trickling down because to people who work thanklessly to do so.

Something about this sentence makes me think about that Rob Auton bit, that before there were mobile phones, nobody had any reason to tell someone else that they were on a bus.

Before mobile phones you never called someone and asked "where are you" because a phone was tied to a location...