This is incorrect.
If you lockdown properly.... a full lockdown with essential workers only... and you do it for the right amount of time... and after the lockdown you restrict movement severely... then you can stifle this virus and then manage it through contact tracing.
If the Chinese had not done exactly this in Wuhan, all of China right now would be suffering terribly - they’re not. New Zealand, a country with far fewer people, locked down just as China did, and now they’re prospering.
These two countries have shown the rest of the world how to manage this virus.
Unfortunately, as with the other coronaviruses, it now appears you can get Covid19 multiple times. This means that a vaccine (IF one can be discovered) won’t have any lasting impact. It also means that herd-immunity won’t work. Herd immunity only works if the people who get sick, and then recover, can’t get sick again. We’re already seeing concrete data that people, just half a year into this thing, have caught this virus twice (consistent with all the other coronaviruses, which you can catch multiple times during your life).
The only option is to shut down. Completely. Then contact trace like crazy. Then watch your borders. If the whole world does this then the virus becomes manageable.