>No doubt some state departments of transportation will line up to buy these new "insights" from Google (forgetting that they actually already buy similar products from TomTom, Inrix, StreetLight, et al.) [2]
Google/Apple probably collect a massively larger amount of data than those other companies, putting those other companies at a risk of losing future revenue.
Between Google and Apple pretty much every car in the US is monitored.
Yeah, Google and Apple do probably have much more first-party probe data of passenger vehicles. But it really depends on the type of traffic data product. For some use-cases, it's more than sufficient for the vendor to buy probe data from specific types of fleet vehicles (like work trucks).
Where Google/Apple's coverage is quite valuable is for near-real-time speeds for atypical events -- say like yesterday's Super Bowl. But that's not what this blog post is about -- this post is about a well-established pattern that can be identified with historical datasets.
All that to say that vendors sell a wide variety of data products to transportation planners, but just because Google is now entering this niche market doesn't mean they'll be "the best" or even realize what their strengths are.
It does look much more like a revenue play. The data already exists, but not from the conglomorates and not as uniformly formatted.