It's a fun thought-exercise, isn't it? I think it's very possible that alien species inhabiting physical bodies who've been able to escape their blue-zone home planets are likely more like us than not. If we analyze the evolutionary trajectory of our species too it's not too far out of the realm of possibility that we're evolving to be more "grey-like", with larger heads, more fragile bodies, and telepathic communication. I think the complication in regard to communication would be emotions. Humans thrive and feed off emotions but highly advanced aliens would have likely engineered emotion out of their species.
Considering how many intelligent non-hominoid species we have on Earth it's also possible that alien evolution could have gone down this path on other blue-zone planets as well but it's unlikely they would be able to escape their planet without the ability to make tools and later build and engineer.
The thought of this all has fascinated me since my earliest memory.
I used to think like you, then I learned that our star-type is pretty rare. The only reason we are the dominant species, is because an Everest size meteor struck the Earth circa 65 million years ago, which set off a cascade of events leading to us.
In fact the only reason we have seasons, is thought to be because of that meteor, if those things hadn't happened, the Earth would have had a different set of naturally selective pressures.
Imagine an intelligent species from a water world, or on a rocky planet circling a red dwarf star (the most common type in the universe). As far as making tools all you need are opposing thumbs and a brain, like crabs, parrots, or any number of creatures.
Damn! I could think and talk about this for hours 😊.
One theory I don't think I mentioned in the video, is professor Brian Cox's. He said he had always thought a great way for an alien civilisation to contact us, would be to leave easily detectable balloons in the atmosphere, as they passed by. Just a kind of "hi, you're not alone" kind of message...
Cg
Ah, very interesting! It looks like I have more research to do. I can't imagine not having this natural curiosity about things but many people don't. We certainly had a lot of UFO sightings in central Ohio in the 1970's when I was growing up and had a few strange first-hand experiences ourselves. We were close to Wright-Patterson air force base so many of these (but not all) could be chalked up to experimental aircraft.