There's not much wrong with being the product as long as you are aware of that distinction. The problem arises when people aren't aware because this in essence takes away their right(option, if you will) to refuse to use the service.

It's just a catchy phrase designed to sound shocking as it suggests some opaque objectification.

Obviously you don't need to "be the product". Selling a shortcut to a bit of your attention makes a lot of money, too.

Edit: And you are always in the position to choose how much attention you grant the apps you use.

> what's inherently wrong with "being the product"?

Products are sold