We are so hardwired for human exceptionalism that we can't even entertain the thought of there ever being something better that replaces us, which is what's has occurred for 99.9% of species so far and makes it a statistical certainty. It's hubris manifest to think that we'll live unchanged until the heat death of the universe.
And who is to say how it should be? You?
And what does it even mean, is the great thing about humanity the last few decades? There last few years? Surely humanity as recent as a few hundred years ago was not already as it should be?
Not OP of your answer, but I'm happy with my life. Still, I can't value humanity much when we're living the fastest extinction even ever because of, well, humanity. And we won't fix it. I'm happy because none of these silly "issues" like AI will matter one iota in a couple of decades.
"A man's at odds to know his mind cause his mind is aught he has to know it with. He can know his heart, but he dont want to. Rightly so. Best not to look in there. It aint the heart of a creature that is bound in the way that God has set for it. You can find meanness in the least of creatures, but when God made man the devil was at his elbow. A creature that can do anything. Make a machine. And a machine to make the machine. And evil that can run itself a thousand years, no need to tend it."
It's hard to see a value in humanity when most of the globe is a giant dumpster fire. We currently have:
1. United States, a corporate-owned two-party clusterfuck, potentially on a brink of failing into an autocracy. Because the world is in post-ironic phase, this is all turned into a TV show for the mass entertainment.
2. Russia, a kleptocracy turned into an authoritarian police state run by an ex-KGB ex-Stasi nazi. Always messed up, badly, waging wars as a hobby. Doing their best to fuck up things abroad so they aren't alone, and fuck things up domestically so people are more obedient (dictatorship 101: people always behave "better", when their base needs are just barely satisfied so their focus is all on survival).
3. Middle East, where all things are so fucked up beyond recognition I don't even...
4. China, another anti-utopia lover's dream, with obligatory facade of "harmony" and "prosperity". Don't know much about their internal affairs, to be honest, but don't see any good coming out of it.
5. Africa isn't doing any better, we just hear and care less about their mess here because we have our own mess at home.
6. A bunch of ticking bombs (pollution, global warming, overpopulation crises) so we won't get bored by the old wars alone.
And all of this stems up from the fundamental issue of human nature. Innate high susceptibility to things that sound nice (aka populism) leading up to blind faith, constantly abused by high achiever sociopaths, toppling societies left and right despite all the checks and balances, wreaking havoc. We know about logical fallacies, but still - en masse/at scale - fail at those, badly. We only realize the writings were on the wall all the time, when we're already stuck deep in the mess we've made ourselves.
The worst part of it? There seems to be no solution. At least not that I've ever heard of. Pandemics showed us that a global challenge doesn't reunite people but rather gets abused to divides them further, so even evil aliens' arrival or GAI-gone-Skynet most likely won't change anything.
Our best chances are achieving global post-scarcity and/or solving death (so, yeah, very realistic goals straight outta sci-fi books /s), but not even those are guaranteed to work - just a slim chance that maybe if those major issues are out of the picture something will change and maybe there will be a slim chance it won't get abused for worse. Transhumanism might be another chance (if our monkey brains are a problem, maybe we can patch them up or possibly hop over to something else) but I have my doubts.
What's to value? That humans have coping mechanisms that lets them just ignore all the crap going around and live happily in their imaginary safety bubbles, until it's their time and the frog is finally notices it's being boiled?
(Please don't get me wrong, zero hate here - except the hate for all the abusers and hate for all the mess happening. I love humans, but I'm deeply saddened that something is really wrong with us that we just can't get our shit straight for multiple millennia, stepping on the same rake over and over.)