Nassim Nicholas Taleb has an interesting point that for human creations the expected lifespan is the same as their previous life[1]. If a book is read 10 years after it's published, you can expect that it will be read for another 10 years.
So for C this would be 44 more years from now, but it gets another extra year for every year it survives, so it isn't far fetched to think C will be around in 2100.