A very widespread implication of this is if you are on a call with a bad actor and are on speaker phone, and you enter your password while talking to them, they could potentially get that password or other sensitive information that you typed.

Assuming it really is that accurate, a real-world attack could go something like this. Call someone and social engineer them in a way that causes them to type their login credentials, payment information, whatever, into the proper place for them. They will likely to this without a second thought because "well, I'm signing into the actual place that uses those credentials and not a link someone sent me so it's all good! I even typed in the address myself so I'm sure there's no URL trickery!" And then attempt to extract what they typed. Lots of people, especially when taking calls or voice conference meetings or whatever from their desk, prefer to not hold their phone to their ear of use a headset mic and instead just use their normal laptop mic or an desktop external one. And, most people stop talking when they're focused on typing which makes it even easier. Hell if you manage to reach, say, the IT server department of a major company and play your cards right, you might even be able to catch them entering a root password for a system that's remotely accessible.