You might have conflated the prohibition on encrypted/coded communication with a blanket ban on data vs. voice. Those frequencies are supposed to be used for public communication, which has been interpreted as a requirement that anyone can listen in (as opposed to any member of the public privately communicating with any other member). See 47 CFR Part 95, plain language voice communication.

These days, I'm not sure anyone would seriously rely on a system that sent only unencrypted point-to-point data, so for that use case your original point stands.