To be the second devil's advocate...
I agree with you, the speed of light is the universal cap, but Einstein with General Relativity and Eddington's eclipse observations confirmed the oddness of space-time...gravity wells and warped space...time being both slow to the point of not moving and moving forward or backward...black holes. Einstein also gave us the cosmological constant, something which bothered him but his calculations cannot work without it, nobody's can. And the world of quantum mechanics and all the oddities of that. He basically struggled the rest of his life trying to find a grand unification theory to pull the large and small workings of the universe together. Nobody has come close. All we get is more speculation that cannot be proven - multiverse, string theory.
IMO Einstein was the most brilliant mind to have ever resided inside a human being...and I have yet to see someone surpass him. Humanity had inspiration in spurts, from Democritus, Aristotle and Archimedes we largely had a gap until Leonardo, Copernicus, Brahe, Galileo and Kepler, and then a brief gap to Newton and then a sort of gap while people digested a Newtonian universe...then the golden age of Faraday, Tesla, Planck, Hubble and culminating with Heisenberg, Eddington, Einstein and Fermi. We are still digesting the Einstein universe. When this gap closes...who knows? I see the people around me and I cannot help but wonder if as a species we are getting dumber by the second.
So, could somebody someday here on Earth (or anywhere else past, present or future) figure out a way to nullify mass and create a more reasonable energy conversion into propulsion possible to propel sentient life to near light speed velocities? I cannot categorically say no, but they have to account for that cosmic speed limit and the conventional rules on mass, energy and velocity IMO make it clear that mass may be the easier variable to tinker with, though how that may occur is a long long way off from being understood.
So, until then...bag n' tag those ET's or talk to the hand!