I also think it's possible that we have been visited by extraterrestrials, but highly unlikely.
I will say however that all of our discussions about the possibility/probability of space travel is based on our current scientific knowledge, from which we extrapolate. It's all impossible until it isn't.
Quantum entanglement provides a possible window into faster than light travel of information at least, even though actual information is supposedly restricted to the speed of light.
I read someone state that it's not that the speed light itself is restricted inherently, but that the medium through which it travels (space) is what restricts it. Never thought of it that way before.
If whatever keeps particles entangled does not depend on travelling the 'space time continuum ' as we currently understand it, then information can travel FTL.
Just some thoughts.