What about hard-of-hearing people?

Text-first is precisely designed for them: no need to decipher a voicemail or talk on the phone — the exchange happens in writing, at their pace. One question at a time, short sentences, no obscure abbreviations: the default style is close to what advocacy organizations recommend. If the person prefers the callback to also happen by text, the lead's status notes it for you. Honest limit: the Pro-tier AI voice remains a difficult channel for this audience — text is the right tool.