There are 7.8 billion people on Earth. A vaccine that saves a few million isn't worth making billions put their lives on hold plus all the collateral damage that causes.
Pandemics of this size in the past destroyed economies as people decided to hide, so you're going to get that damage no matter what. By getting it under control, the damage is minimized as many countries that followed best practices has shown.
Those countries that tried to do what you suggest are the ones with the longest economic downturns.
You should read about pandemics of the past.
And as very solid evidence from experts, the famous IGM economists poll of most of the world's top economists covered this exact question [1], which I'll repeat:
"Abandoning severe lockdowns at a time when the likelihood of a resurgence in infections remains high will lead to greater total economic damage than sustaining the lockdowns to eliminate the resurgence risk"
100% of them selected Strongly Agree (41%) or Agree (39%) or Uncertain (14%), not a single vote on any part of the Disagree spectrum, which is nearly unheard of for a question in economics, and these responses were also rated highly confident. Check other questions and polls to see how rare this strong of a response is.
Shortsighted action ignorant of the history of economics almost always makes things worse.
