That can be a noble goal, but I wouldn't be so hand-wavy about how people understand words and their meanings. I'm firmly in the camp that the mRNA covid vaccine was a wonder of modern science, and on the whole it had net positives for society. Don't misunderstand, it was not rolled out, or messaged perfectly and wasn't without risk that we're likely to wrap our arms around some day in the future.
But we can learn from the experience. And in my view, telling a captive, emotional, and concerned audience "we have a vaccine!" and then not absolutely being a broken record about what that means was a miss.
My point was that there was absolutely nothing different about the covid vaccine in this regard from literally any other vaccine. So I'm not sure why you're putting it into a special bin here.
If the point is that the average person is uneducated and doesn't understand how vaccines work, sure. But if the solution is to use a different word, that new word would need to be applied to every vaccine on the market. And what's the point if that's the case?
Also, I don't recall ever hearing people with actual knowledge claiming it provided a cloak of invulnerability. So again, I'm not sure what those people should have done different. I'd agree that the media distorted scientific truths, but they always do that.
But we can learn from the experience. And in my view, telling a captive, emotional, and concerned audience "we have a vaccine!" and then not absolutely being a broken record about what that means was a miss.