Why do people still believe Faster-than-Light travel such as Wormholes and Warp Drives are still possible?

Arent you assuming things are impossible given the elements found on earth and current level of technology? For example what if there were a naturally occurring element found on a planet not far enough away to necessitate FTL that we could reach eventually that opened up new power generation possibilities or something. People have always thought all kinds of things were impossible like landing on the moon and affordable salon grade hair products. I believe whats more likely than some type of FTL is just fusion powered ships where the crew sleep in cryo pods for year long journeys