The reaction is that people disable notifications. Only, it’s really hard to get data on this as a publisher. You just, silently, get decreasing click-through rates on subsequent messages.
“This app would like to send you push notifications!” -> Deny. “It’s just for (legitimate reason)!” Fine. “And marketing!” -> Uninstall app. “Are you sure?” - I’ve never been more sure in my life.
There’s a setting in chrome & Firefox to block websites from even being able to ask for the ability to send notifications. It’s one of the first things I set when I setup a new computer.
It's funny because in a group crowded channel there is feedback so long as you are part of the channel. But I think even in those circumstances, the feedback you get from the noise of everybody else, you don't interpret that as the same thing as you sending just "your one message".
Humans are really bad at understanding distributed harms.
A crowded channel grows noisier, but there's no feedback.
Can a gamed metric become valuable again, or does it likewise expire?
"Trust arrives on foot, but leaves on horseback."