People really don’t understand how ridiculously big the universe actually is.
Look at this
That’s our solar system, right?
Well, no, not really. Our solar system actually looks like this.
Like if you went to Pluto and looked back towards the sun, that is pretty close to what you would see.
The nearest sun to us is Proxima Centauri.
Which is just around the corner at 4.2Light years. Why that’s practically in our back yard. Well, not really. That’s actually around 24,690,000,000,000 or 24.69 trillion miles.
Travelling at light speed would take you nearly 5 years to get there. But, since we can’t even come close to an appreciable fraction of light speed, we would need tens of thousands of years to get there.
The reality is that the miles (or Kilometers if you live in a non-stupid country) between solar systems are so insanely far that it is highly unlikely that any sort of biological life would have been able to get past them.
It is possible that we just don’t understand physics enough to make it happen. But it’s also possible that we just can’t go much faster than we can right now. And the reality of that is that we’re not getting off this rock. And neither is any Alien species getting off their rock.