Modernize the system how? Like do you have explicit steps on how to modernize it and what needs to be done?
Already exists, it's called TCAS
https://www.twz.com/news-features/heres-what-air-traffic-col...
So there's already tracking on a map that's available to the pilots. During landing, pilots are looking outside and not glued to their instruments.
The real issue is trying to cram too much aircraft in such a small space and time.