I can see benefits for SAR with ADBS because the GPS history will be sent to a central repository. Should make finding lost planes a lot easier and more reliable.
Sure thing Pete, planes go missing within radar coverage all the time ...
Also, ADSB receivers are becoming so cheap everyone can have a form of TCAS.
Not all of us want one. I gather you are one of the “screen starer’s” that are so common these days.
I don’t particularly want one of these things in my bugsmasher, I see it as pointless expense. I am also not that enamoured with being tracked wherever I fly.