I discovered a long time ago that the benefits of Lisp are more than outweighed by the frothing zealotry of a lot of the members of the Lisp community that just can't see that almost every single language design decision is about tradeoffs and not about right or wrong.
Lisp seems to attract people that are a little mentally imbalanced.
> By ratio of useful, must have programs (including code used in space missions), C wins, and Lisp doesn't have much (if anything) to show for.
Those programs may as well as have been written in brainfuck for all I care. You can write as many programs you want in a language, that doesn't make that language better.
At the very earliest stage in their functioning, C programs go through a pre-processor that is so horribly stupid it was completely removed from D. Thats just the start of it...
The burden of proof doesn't change sides based on ...age. Algol68 is older than Haskell, but still most experts will agree that Haskell is better.
As for it being "up to C and the other new languages to prove their worth." that's what I just said. By ratio of useful, must have programs (including code used in space missions), C wins, and Lisp doesn't have much (if anything) to show for.