As far as we know, there's no way to get around the lightspeed limit, which implies no matter how advanced a civilization gets, they would be constrained by physics and available resources - so no warp drives, no stargates, nothing but rockets and things that work like rockets, and generations of travel between the stars.
If that's the case, it any form of space travel, much less long term interstellar travel, might be an exception rather than the rule for intelligent species. We only assume that expansion out into the stars is a natural consequence of progress due to biases we have regarding biological and societal evolution, but space isn't just a bigger ocean.
We can't really extrapolate the likelihood of visitation by extraterrestrials from the historical tendency of cultures to encounter one another on our own planet. Given the vast size of the observable universe and the unremarkable nature of the Earth (from which we've only been broadcasting signals for a fraction of an instant, relatively speaking) it's not at all surprising that we wouldn't see anyone or that no one would see us, much less stop by for a visit.
Although "Quantum Teleportation" could that theoretically be used to "teleport" a spacecraft FTL?
Everything I've ever read about quantum teleportation says no [0..2]. Even if state changes are instantaneous, the transmission of information itself is still limited to the speed of light (and a ship counts as "information" in this case), and the process of quantum teleportation would require some classical communication channel to transmit state.
All that notwithstanding the amount of energy you would need to "entangle" an entire ship in the first place.
[0]https://www.quora.com/Is-the-any-possibility-that-Quantum-Te...
[1]https://medium.com/starts-with-a-bang/ask-ethan-can-we-use-q...
[2]http://www.askamathematician.com/2013/01/q-what-is-quantum-t...
And what's that Pentagon video of some super fast object? https://www.nytimes.com/2017/12/16/us/politics/pentagon-prog...
I think if ET was real most people would still care about the same things (because consider that 2000 years ago we are warlike, violent, superstitious, gullible, flawed, selfish, kind, etc, and 2000 years later, after organized religion, industrial revolution, international travel, internet, long lifespans, mobile phones, we are still the same). Maybe 10 - 20% of the population would adopt ETs as some sort of "god" / higher power (but there are ppl who do this anyway, even now). I don't think much would change, but ppl would try holding their governments to more accountability ( why don't we have that tech, why have you kept it secret ), but like most protest movements recently, it will probably be pretty ineffective. I use to think there will be large scale civil unrest, but now I think, people really won't care.
But if there is that tech on Earth, then our military has to make it a priority to obtain it (because what if someone else also has it), so there's that consideration, which could justify keeping everything secret (what if everyone had a UFO and could fly anywhere they wanted at 20,000 km/h? probably chaos, an upending of the order ~ but maybe not. We thought individuals having access to all information, and a publishing platform, would make individuals vastly more powerful, but that hasn't really upended the order. If anything, the State has become more powerful because of the internet.)
But UFO travel would sure beat 15 hours across the pacific in an uncomfortable aluminium tube.