I understand the analogy you are attempting, but it is wrong. Nobody believed, 70 years ago, that the technological challenges of a trip to the moon could be met. It was known, however, that it was possible in theory.
FTL travel is theoretically impossible, not merely impossible in practice. This is because the speed of light is fundamental to the very structure of spacetime itself.
It might be possible to cover great distances by using quirks of spacetime geometry (eg the aforementioned wormholes), but the actual motion will always be slower than light.