The reason research like this exists is because we don't know what we don't know. Results like these are meant to stoke curiousity so that more research can be done.

So on and so forth until one day you have horseshoe crabs saving millions of lives. But they didn't know that would be the case when they started researching them crabs, function comes after exploration.

I mean on top of answering fundamental questions about the nature if reality, proving that the universe is a black hole would necessarily invalidate almost every religion. That fact alone would upend society, and probably in a bad way.

Also, if the universe is a black hole that means the universe is capable of reproduction. If the universe reproduces, there is likely no limit to the number of times it can do so. If an infinite number of universes spawn an infinite number of children, it basically establishes reincarnation as a fact of life.

And that's ignoring all the philosophical implications such a discovery would immediately raise.

Maybe it wouldn't change anything. Maybe it would change everything.

Astronomy is critical towards understanding the foundational principles of reality. Observing the universe around us is the guide for where physics should follow

And I think most people would agree that understanding how our world works, the physics of it all, is very very useful in unforeseen ways. Cannot hope to make a circuit if you don't know how electricity works, right?

Am I meant to stare up at the sky from 8:15 to 8:30 every other night with my mouth agap while I try to wrap my mind around the spacetime bubble we all exist on the surface of?

At scale that sounds better for society than going to church. We need a little more memento mori (memento minima?) in modern life.