"We will only keep your personal information for as long as it is necessary for the purposes set out in this privacy notice, unless a longer retention period is required or permitted by law (such as tax, accounting, or other legal requirements). No purpose in this notice will require us keeping your personal information for longer than the period of time in which users have an account with us.
When we have no ongoing legitimate business need to process your personal information, we will either delete or anonymize such information, or, if this is not possible (for example, because your personal information has been stored in backup archives), then we will securely store your personal information and isolate it from any further processing until deletion is possible."
There are a few good points in that response and a few I don’t. They also concede a couple points, and complain about somebody who reposted that article (but not the original author I linked, thankfully).
To address your question: For example, sure, maybe Google does cache data but…