If you run a records company I assume this might be worth some money
The data in this example was going to be made public anyways. All the examples of prediction markets are predicated on them becoming public. You not only need the info, you need the info before it becomes public.
and that's exactly how the Google engineer made money, right? He knew it beforehand, and once it was made public other people did too
Realtime access to internal Google search data may help you predict a lot of things that might be worth money, for example there's an existing market where companies buy usage estimation for competitors products (not though Google). I don't see why so many people are completely sure this information is worthless
For example, d4vd is a famous musician, and search stats may indicate his potential popularity and future record sales.
Or the public may be searching his name to find out more about the body found in his car, and the subsequent murder investigation and arrest.
I wasn't really aware of that as I guess I am not the target demography. However, I can think of multiple ways of making money off this information, I still don't see why people are so sure it is worthless