Umm I think I'll just delete you instead

Well I don't think you can turn off receiving voice messages in other messengers, either. It's a weird premium-only feature, but eh, at least they're not making things worse compared to the baseline.

You can just turn off receiving all messages from any user. This is specifically for people who told their friends that they don't want to listen to voice messages and want texts, but friends still use voices. Every one I know has a friend like that.