> ” I've found myself using this pretty actively with small groups of friends”

Would people listen to these small updates?

Audio is pretty big in WhatsApp. But it’s widely accepted that audio messages are good for people who send it and bad for who receive (it is a hassle to listen to it, even at 2x, comparing to reading a text message).

Also, your use case seems very well covered by WhatsApp and Telegram.

I am part of a Telegram from a famous writer where he only sends audio messages (one-to-many, closed threads, only accepts emojis). It is hard to differentiate a product enough as an audio only social network to beat Telegram and WhatsApp on most use cases.