ATC isn't the only party who needs to see the aircraft IDs.
As a pilot, it's valuable to be able to see tail numbers to help correlate what I'm hearing on the radio with what I'm seeing on my displays. I can guess who's who from position reports, but seeing the tail number leaves no ambiguity.
There are also some smaller facilities that use ADS-B to monitor traffic, but aren't networked into the national ATC radar system.
Aviation events will also setup their own temporary control tower, and frequently use ADS-B as an aid for sequencing traffic. (Again, without access to the national ATC radar network.)
For folks who need privacy, there are a couple options that already exist - UAT privacy mode or private Mode S addresses. Though notably, both of these are only available options for domestic flight within the US.
Aircraft systems I know don't show the callsign of TCAS targets (although they should be able since it's in the extended mode S reply). I think only iPad based systems in small general aviation typically do that? I've never felt like I missed that information when flying.
As a pilot, it's valuable to be able to see tail numbers to help correlate what I'm hearing on the radio with what I'm seeing on my displays. I can guess who's who from position reports, but seeing the tail number leaves no ambiguity.
There are also some smaller facilities that use ADS-B to monitor traffic, but aren't networked into the national ATC radar system.
Aviation events will also setup their own temporary control tower, and frequently use ADS-B as an aid for sequencing traffic. (Again, without access to the national ATC radar network.)
For folks who need privacy, there are a couple options that already exist - UAT privacy mode or private Mode S addresses. Though notably, both of these are only available options for domestic flight within the US.