I’ve been harping on about this for a while now… ADSB OUT is next to useless without ADSB IN.
Unless you are in direct contact with ATC then you are back to see and avoid. (But as we’ve seen even if you ARE in contact with them, it may not help!)
IN gives you a fighting chance to see someone in advance.
The sooner everyone gets ADSB out, the better, even if it’s just a SkyEcho.