I like the idea, but it will never take off. People are fundamentally lazy when it comes to these things. Look at the surging popularity of voice messages in some circles, shifting the burden of communication fully to the receiver. Even if you had the feature, I'd wager most subject lines would stay empty, or just contain the bare minimum like "hi".
That’s ok. Metadata improves context but isn’t mandatory. Some people want it, others don’t bother.
It’s like sending a calendar invite. Sure, you can send an invite with nothing but your email address and a date+time. But many people would find an empty invite a bit rude. It’s just polite to include some context about the meeting. The phone call should evolve in that direction.
If it's not mandatory, then what's the point? You can already send text messages if the message is important. And since it's optional, both spammers and your lazy family will leave it blank making it useless to filter out spam.
It doesn't have to be a burden. My watch already provides me a quick-select list of responses. So when I make a call, instead of one generic send button, how about two? One of them labeled "this is a emergency" or something like that. Maybe even a little list of a half dozen of the most commonly used subjects, so I just click the one that matches.
No reason to make people work any harder than they do now.
But if other people are lazy, why would I entertain interruptions from them? I generally don’t do any work voice or video calls because, simply, they are an interruption. So they need to have an agenda and be scheduled. And indeed, I do not listen to voice messages; type it out or don’t send it at all.
