For reasons unknown, Google has removed the Uber integration within the Google Maps app. Google added the ability to book Uber cab within Maps back in January 2017; this functionality allowed users to identify their route, then check Uber prices and request a ride without leaving the Maps app.
With this integration, users had the option to avoid installing Uber app since Maps app offers a way to book the cab, so it is safe to say Uber, rather than Google, might be behind the decision to block Maps integration. We haven’t seen any confirmation or announcement about this move either from Google nor from Uber.
Uber integration within Maps was pulled from Google Maps for iOS back in August last year, but Android never lost the support until February as well. Google Maps Help page, Google simply says “you can no longer book Uber rides directly in Google Maps. With Uber certainly preferring customers to use its own app instead of Maps for booking cabs, this move seems not so surprising.