i am not claiming that it is forbidden to remember things. but the laws against recordings are pretty explicit: https://en.wikipedia.org/wiki/Telephone_call_recording_laws

if you make a recording, transcribe it, the delete the recording, it's probably hard to prove you made a recording. better yet with todays technology you can probably make a transcription live. i don't know if feeding he audio into a transcription tool counts as recording.

but the example was to use a recording in court. if you do that then everyone knows.