Even if it were the case that civilization must trend toward some humanist ideal utopia (which seems like a dubious proposition), there’s still an excellent chance that the human race wipes itself out long before we get there. Let’s think about a few options:
Right this minute, we could have a full nuclear exchange which renders the planet basically uninhabitable - nuclear winter, fallout, the collapse of every economy and monetary system in the world. It’s a lot less likely than it was back during the Cold War, but the technological capability still definitely exists. I don’t know if we’d be able to claw our way back to civilization after an event like that, but if we did, I don’t see anything keeping us from doing it again, and again, and again, blowing everything up every few hundred or thousand years, and never reaching that ideal.
In the moderate term, we still haven’t done much to cut back on global warming. You may have heard of thermohaline circulation? And how there’s a decent chance it will shut down if we don’t stop pumping CO2 into the atmosphere? I heard that outcome described as “Everything dies, and the Earth smells like twenty billion rotten eggs”. I’m not sure if that would end human civilization, but it would definitely be a setback to our utopian ideal, insofar as we would have to conduct our perfectly happy lives wearing gas masks anytime we went outdoors, assuming you can go outdoors at all.
In the long term, there’s plenty of large scale non-manmade disasters still ready to help rid the Earth of its hairless monkey infestation;
The Yellowstone Supervolcano is about due. When it blows, it’s going to take most of the western half of North America with it.
We don’t actually know how many potentially Earth-threatening asteroids are out there, only that it’s a lot and that if one decides we need to go the way of the dinosaurs, there’s not much we’ll be able to do about it.
Heck, we could have a hypernova detonate in our galactic neighborhood, and just irradiate every living thing for lightyears in every direction.
No, I’d say there’s nothing inevitable about an post-scarcity technological utopia. I don’t think it’s impossible either, and I enjoy reading about the possibility, but in the end, it’s clearly at best only that - a possibility.