Vaccines are a lot less likely to kill you and don’t actually give you the virus, which is the goal. Getting the virus means you have a chance of dying or permanent injury. And, possibly more important, you are just one more vector that can further spread the disease, increasing the chances of mutation or killing or injuring someone you know or love. The goal is to stop spreading the disease so we can all get on with our lives. You don’t do that by getting the disease and possibly spreading it. This isn’t hard.
A thought experiment: In what way is ‘herd immunity’ achieved via mass infection rates in the general population in any way distinguishable from ‘the worst case scenario‘ of the disease’s potential spread? And when has that strategy ever been successful in human history? We did nothing to stop smallpox and allowed it to run rampant (because we didn’t know how for most of human history), but it stayed with us for thousands of years and we never achieved herd immunity. What finally stopped that? Oh yeah, a vaccine.
edit: fixed typo.