It's right there in the privacy center. The answer is quite unambiguously yes by the way. (This is for the Gemini app):
"How your data is used
Google uses this data, as described in our Privacy Policy, to:
Provide our services
Maintain and improve our services
Develop new services
Personalise our services (learn more)
Customise our services
Communicate with you
Measure performance
Protect Google, our users and the public
These uses extend to the generative AI models and other machine-learning technologies powering our services."
"How your data is used Google uses this data, as described in our Privacy Policy, to:
Provide our services Maintain and improve our services Develop new services Personalise our services (learn more) Customise our services Communicate with you Measure performance Protect Google, our users and the public
These uses extend to the generative AI models and other machine-learning technologies powering our services."