Well the main feature of the vaccine over the actual virus is that the vaccine doesn't give you covid. The vaccine doesn't cover all of the multitude of compounds your body might recognize on the virus, but it covers enough for most people to build a better immune response to the actual virus than nothing. There is the issue that the viral strains are mutating and so over time so that a recently-vaccinated person today will probably do worse than a recently-vaccinated person 6 months ago, but there's not really much you can do about that.
I never said that humanity couldn't survive without a vaccine. Clearly we can. We also can survive with rotten meat and with poor shelter and with rampant war and famine. Sure a larger portion of us would die, but humanity would certainly survive.
Anyway my point was that when you're infected with a virus, your body basically builds up the ability to recognize certain proteins that the virus expresses and uses that to fight it off. It takes time to build up the ability to fight it off. The vaccine exposes you to basically the same proteins so that your body is able to identify and fight off the virus more quickly after infection. So really the vaccines are just priming your immune system so that it can better do its job.
I'm not really sure what your point is. We shouldn't try to help those with weaker immune systems survive? How far should we take this? Should we as a society not make an effort to help the physically disabled, the old, the blind, etc. survive? Looking to the wild, basically no members of those groups survive. Is that what we should aim for?
To be fair, this is what the vaccines do.