>My reasoning to assume so is a wholly intuitive instinct that all ultra-high technology societies converge in their moral and ethical norms to a common limit.
We don't know that. We also don't know if the prime directive of aliens is the same as ours. By that I mean that whatever aliens may be visiting us may not be competitive whatsoever. Maybe their planet didn't have the same explosion with life that ours did so it's relatively empty of competition. In this case cooperating with others to expand as an instinct would be much more beneficial than competing. There is also no tangible evidence of the cosmos swarming with life, on planets or traveling so it might also be that -given how long it takes for planets to form stable orbits and how long it took on Earth for humans to appear and develop instruments to observe the universe- the universe is for the time being relatively empty of life. Some people revisited the drake equation and approached it as a coin flip: Sure there is a 50/50 chance but it's either/or, so based on their calculations the most likely scenario is for 0-2 times life forming on our galaxy. And FTL is still science fiction so it might be that the only species that can visit us are coming from other galaxies and have evolved to survive for billions of years. At the same time thanks to kepler we now know that planets with the characterists of earth are rather rare as are solar systems like ours. But there are a myriad of other planets with conditions too hard for humans but good enough for life found on Earth. In this case it might have been that some sort of life exists in the cosmos but it evolves much more slowly compared to us and thus needs a few extra billion years to reach space travel. So maybe the universe is experiencing it's first explosion of life and we are one of the first multi-cell organisms or step out of the water. Who knows.
Also we don't know how technology would have evolved should it be that Earth had a different composition. Like for example metals are fairly rare on the crust but yet they are fundamental to our function. Maybe a planet that has a 10% metal crust would have evolved towards electricity much faster than us. Or a planet with lower gravity and lower or no magnetosphere could mean that whatever species developed there could have achieved space travel much faster and easier thus increasing the incentive( in human terms) of developing ftl. Right now ftl is sci-fi for us but remember that yes, it was the military who developed the internet but all the applications and the development of the science behind it came once more people could toy with it.