Is there any evidence that big data will be valuable for any other coin aside from BTC?
We are still in the process of defining what "big data" will mean regarding "bitcoin under servicenode supervision".
It's not just a question of "is there is a market / buyer who will be interested in this data",
it's also about what data we shouldn't be gathering in the first place since it goes against principles of privacy, security and decentralization.
It'll be quite a balancing act.
About your question, if something works for bitcoin why shoudn't it be applied to other coins too.
The bigger the marketcap of a coin, the more valuable big data becomes.