Earlier quoted context omitted.
> The example on web.dev is a chat app that would automatically set an active/away status: seems useful! I have an alternative way to do this. Check if a user hasn't interacted with your text box in x period of time. If they haven't, set them to away. I'm sure people can come up with other methods too. It just seems like there's a thousand ways to skin this cat that don't have the same potential for privacy issues.
But this isn't adequate for the IM use case at all? I spend the bulk of my time not focused on my chat app tab(s) but I definitely want to be reported as 'available' by those chat apps, because I am if someone messages me.
Even only with public group messages, you can figure out some others sleep schedule or when is he/she mostly active if you have enough data. This api will only make things worse because it trace you 'actively' now.
Besides that, you are able to send message when other is not here is the biggest point of a text chat app. If you must chat instantly, why not just call with phone?