“Objective worth” is a bit of an oxymoron, because worth is up to your value judgment.

If you’re questioning the “evolutionary imperative” that organisms want to pass on genes - one fairly human trait is that a lot of us can consciously diverge from that instinct, either fulfilling that need by passing on our legacies socially rather than genetically, or just not looking to pass anything on at all.

Something we have in common with other mammals is we prioritize whatever experience is in front of us. Anyone who’s directly affected by catastrophes and strife will have different beliefs than people who aren’t.

So if objective worth has no neat answer, what’s left?

I’d say it’s interesting to have so many different subjective experiences in one world, with a language-based society able to communicate and share many more varied experiences than most animals. Interesting isn’t inherently good or bad, but if nothing was good nor bad then nothing would be interesting.

So yea. Human life is entertaining. We’ve got that going for us!

P.S. If you’ve ever lived in a city whose infrastructure is strained by overpopulation, you don’t necessarily view declining/shifting populations as a bad thing.