What is the point of our lives? Collectively we can contribute changes that are good, but those good changes only benefit the living.
We all die.
There is nothing guaranteed after death, and nothing significantly proven that says there is anything after death.
So really, we have absolutely no logical purpose to do anything at all, when really all we are is an organism acting reflexively to procreate, eat food or survive. Which ever of those options.
So we exist for what purpose?