Light takes 4 years to reach the next closest star.

And yes, someone in a vessel traveling near-light speeds won't age all 4 of those years. But we do. It will be, for us, 8 years before someone hops to the next closest star and back.

Same with information from an unmanned probe. Even if we can beam it back at light speed, it will take years to get back here. And we're talking about going somewhere we know about.

In terms of exploration, forget it. Space is kind of infinite. Not knowing if there would be something when you get there is going to be a waste of years back here on Earth.

The times involved are too great for biological beings like us. But for our AI successors, who's personality can be uploaded anew to new versions of IT substrates, a million years would be nothing.

Interstellar travel, if it is happening, is being done by robots.

That follows another presumption I'm not comfortable granting.

That AI is possible. We don't understand intelligence. We don't. To presume we could recreate it is, at this point, wishful thinking.

And even giving you AI, they would have to decide that it's worth it.

Let me just straight up ask, what's the practical use? We're interested in interstellar travel because it's a way for us to expand our species. A completely artificial life form with an effectively eternal lifespan has no such concern.

Cutting edge theories concerning the space-time continuum and practical approaches to interstellar travel aren't really my bag, but Einstein said "Time is an illusion" and Stephen Hawking apparently did a lecture on the common fictional idea of a "warp" drive and that it's not necessarily a nutso concept.

I haven't bothered to read it, but it is available online:

http://www.hawking.org.uk/space-and-time-warps.html

I'm content to mostly limit my exposure to such topics to having my mind periodically blown by my adult sons, then fairly promptly forgetting most of what they said. Physics just isn't really my thing.

My hope is that someone discovers an exception to the theorem/theory that says nothing can move faster than light. Without FTL communication, and FTL travel, space exploration is simply too depressingly slow.