I've always assumed SETI was a project to crowd-source break encryption for some agency. Of course they are on the wrong frequency. They picked the quietest frequency which would of course be reserved for emergencies
that we probably could not even comprehend and such emergencies may only occur once in a billion years. I would rather expect them to take in the entire noise floor of all frequencies and apply pattern recognition to the entire spectrum
which may not even be possible with our very limited tech. We may not even be able to perceive 1% of the full spectrum and that is assuming that frequencies are how people communicate across the galaxy. I would honestly doubt this as stars and other objects generate a lot of RF and light noise.
Communication could rather be something to do with dark matter, quantum nonsense, morphic resonance which our scientific community are not intellectually mature enough for, super-strings, others... Great filters may prevent us from ever finding the answers.