Rather the opposite isn’t it? What you’re saying is ‘regardless of relative benefit or cost, humanity would make the decision to do interstellar travel - because reasons’.

I’m pointing out that relative benefit and cost matter and tend to drive decisions - and that the massive cost with (currently) no plausible benefit which could outweigh it, makes it unlikely we would end up taking that course.

Unless we discover new physics, or new ‘value’ somewhere which would justify it.*

Energetically, for instance, even if we found a planet of pure most expensive thing we can think of (except perhaps for antimatter, though that is a more complicated discussion) just a few light years away, it would never be economic to go get it based on our current understanding of physics.

Even sending a physical probe would be of dubious value, especially considering everyone who would be alive or benefit from anything it could ever provide (including information) would be long dead before we could even find out if it could talk to us over those distances or had arrived.

This is so obvious, btw, that sci-fi writers always have to come up with new physics (or outlandish extrapolations of current thoughts on potential physics - see the Expanse’s Epstein drive, or Star Trek warp tech and subspace communications) for the story to be even a little plausible or interesting. [http://toughsf.blogspot.com/2019/10/the-expanses-epstein-dri...]

And it always has to be a mcguffin, because otherwise the whole story falls apart.

For example, in The Expanse, the Rocinante’s drive would have to output 60+ TW of power for even a moderate burn (2G). Something even the most basic mining rockhopper is supposedly capable of, and folks are regularly shown in poverty type living conditions while being those rock hoppers.

The amount of power produced from just that one engine in that universe in an hour or less would be sufficient to distill enough water, power enough hydroponic grow farms, and synthesize enough chemicals, to feed and hydrate literally hundreds of millions of people. Maybe a billion, if sufficiently efficient.

The United States currently consumes a total of 4 trillion Terawatt hours a year [https://www.eia.gov/energyexplained/electricity/use-of-elect....], and at that engines moderate 60 TW power output level, it would produce energy equivalent to our current entire yearly electrical energy usage every 4 minutes. And they’re shown, in context, doing half that rate as a matter of course for weeks. Even if we converted that to electrical energy in the most absurdly inefficient way possible (boiling water to drive steam turbines), it would produce that degree of electrical power every 15 minutes.

Does the Expanse make any sense at all, if each individual ship is burning more than the energy equivalent of all the clean water, food, drugs, and electrical power the entire Earth needs for a year every single week they operate normally? Or for some of those ships, every minute? Especially when there are shown to be thousands or even hundreds of thousands of such ships operating at once, by a vast array of different powers and interests?

And that Earth, despite having access to all that tech, and building 1000s of those engines (at least), grows crops in open fields and suffers massive famines due to… winter conditions? Due to an asteroid impact? And sometimes just because? And has severe water rationing even for the political elite?

Earth is show to have a pretty dysfunctional (and neglectful) political system, but even they couldn’t pull that degree of insanity off.

And belters worry about using mirrors on Ganymede, when just going to and from Ganymede requires using 4+ orders of magnitude more energy than they would if they used enough grow lights to be getting complaints from Earth about the light pollution.

And a 10,000 year voyage at slow rates to go somewhere that has nothing that justifies the insane cost to do it, with no ability to communicate on timescales equivalent to even the whole of human recorded history, is not a very interesting story. Such a voyage, based on our current track record with technical reliability or social stability is even less likely to succeed.

It’s the economic equivalent of
heating your house by burning shovel fulls of
$100 bills in your fireplace - because you can’t pay your $150/month heating bill.

Even Mr. Musk eventually decided he’d rather buy Twitter than actually try to colonize Mars, yeah? And relatively speaking, Mars is right there and way friendlier and more interesting in every way than interstellar space.

Actual interstellar space travel seems more and more like the equivalent of the 50’s idealism around powering your hairdryer with a micro-nuclear reactor.

* Notably, sometimes ideology and propaganda can push society into doing really weird things. But even the Crusades had a real macroeconomic and sociological basis for why they needed to happen. So maybe at some point, sending politically problematic ‘colonists’ into space to die will be worth the cost. And some might even make it! Eventually. But chances are, we’ll find more cost effective ways to do it.