If you enjoy the game, play the game. Don’t boycott/withhold because they figured out an additional use for data that didn’t previously exist.
Another way of viewing this: GoogleMaps is incredibly high quality mapping software with lots of extra features. It is mostly free (for the end user). If no one uses it, Google doesn’t collect the data and nobody can benefit from the analysis of the data (eg. Traffic and ETA on Google Maps)
There’s no reason to hold out for a company to pay you for your geolocation data because none of them offer that service.
I wish it were that simple but I think it's reasonable to hesitate. We don't know what these models are going to be used for. If by playing you're unwittingly letting something powerful fall into the wrong hands, maybe play something else.
(Generally speaking. I'm not trying to throw stones at Niantic specifically here.)