I don't know about twitch but I work for a streaming company and we're using the page visibility API mainly to lower video quality when the user is not actively watching the corresponding tab for more than a minute.
This allows to keep audio while lowering bandwidth, CPU and memory usage.
So yes it may be used for nefarious purposes but it also provides very nice features in a media streaming case.
This allows to keep audio while lowering bandwidth, CPU and memory usage.
So yes it may be used for nefarious purposes but it also provides very nice features in a media streaming case.