COVID is almost certainly never going away. It will become endemic, joining the other endemic viruses such as the couple hundred cold viruses (including 4 other coronavirus that were once deadly pandemics) and the various flu viruses we reluctantly live with. Something we all get several times over our lifetime, that most of the time just make most of us pretty miserable for up to a week or so.
How many people die during the transition from pandemic to endemic depends greatly on how risky it is to acquire your first immunity, and how strong that first immunity is when it comes to preventing hospitalization and death. The lowest risk way to acquire that first immunity is by vaccination. It's also the way that provides the highest chances of strong immunity--when you acquire it by an actual infection it depends on how severe the first infection was.
So yes, mass vaccination gives us the best chances of returning to normal sooner with less death along the way.