I think it's an awesome idea. Not a person on the planet can say with any form of certainty that some type of FTL will never come to age. First, someone needs to prove that technological development will stutter to a natural grinding halt, because all the universe's secret tidbits of knowledge have already been plucked from the cosmic apple tree.

The question then becomes: is the accumulation of all potential knowledge finite? That's an even harder concept for me to grasp, probably harder still than "what happened before the big bang?"