Agree on top-of-funnel, qualification can only sort what you let in, and filtering by the stack a company already runs is a sensible signal before the bot ever opens its mouth.

On voice notes: we pull the audio off the WhatsApp media endpoint, transcribe it, and feed the transcript into the exact same qualification flow as a typed message, so the path never forks. Two things we always add, a quick acknowledgement while transcription runs so there is no dead air, and reading critical fields like names, numbers, and dates back to the lead to confirm, since that is where transcription quietly gets things wrong.