Track and trace will only delay at best.in conjunction with a vaccine, it might.
There are going to be a lot of people around without vaccinations for a relatively long time. How long does the vaccine last? Who knows. How long does natural immunity last? Who knows? The virus will continue to circulate. There will be outbreaks, and new strains. We will need to contain and squash those outbreaks (a la NZ, China, Taiwan etc) for some time to come, I’d imagine.
There's absolutely no good reason to think immunity won't be long term or permanent.