To make it easy to understand my point of view, I am going to go slowly:
1. The Universe is thought to be around 14 billion years old;
2. The Solar System, where we live, is thought to be around 4.5 billion years old;
3. The speed of light is 300,000 km/s (kilometers per second);
4. To travel from Earth to the nearest Star would take 4.5 years traveling at the speed of light;
— That would require the ship to be able to contain life support of some kind for the entire trip
5. The Milk Way; our Galaxy, is thought to be 100,000 light years in diameter; and 30,000 light years in thickness;
— To travel from edge-to-edge, you would need to spend 100,000 years at the speed of light.
— To travel from bottom-to-top, you would need to spend 30,000 years at the speed of light.
6. The Milk Way is thought to house about 200 billion Stars and the closest one to our Sun is 4.5 light years away;
7. Life on Earth, per my understanding, took somewhere around 2.5 billion years to make us, the Homo Sapiens;
— Earth had to have the right “ingredients” arriving at the right time for the “life recipe” to emerge. And, yet, Earth, apparently, is located in the right spot within the Solar System to have made possible the “recipe” to work accordingly.
The chances of similar feat in another Star System is pretty much ZERO!
You, the reader, scientist or not, might argue that “space can be bent”; “worm holes can be used to travel”; “teleportation is possible”; … oh well, these are all science fiction.
You, the reader, scientist or not, might argue that there are more advanced intelligent civilizations out there. Oh, well, sure that you could believe that. But the chances that any possible advanced civilization was able to produce a ship that can travel for thousands or millions of light years with enough life support … within the past 14.5 billion years ….
And, yet, that lucky advanced traveler to find Earth …….