> Our information diet is only as useful as is relevant in future

I think there are situations where ephemerous knowledge is useful. For example, knowing about a security vulnerability: its profitability is much higher before the issue gets fixed, which can happen anytime (be it two hours or two years).

Another example: imagine you know insert-influential-billonaire is going to tweet about insert-trendy-currency, this information is completely irrelevant for the future, but you can certainly use it to make money.

It's worth mentioning these two examples, however, can provide longer-lasting knowledge as a by-product too.