[Wyverald]

One reason: Google needs this info in order to give it to you.

Sure, you can acquire this info via some other means, but that would mean someone else having it.

[dredmorbius]

Google could hold the data encrypted against a key you control and they do not. You'd have access to the data, and could control specifically when and to whom it's released.

It would continue to be backed up on Google's servers.

[vilmosi]

Yes but then why would they ever offer such services without monetisation opportunities?

[wingerlang]

You could implement it locally though.

[Klathmon]

I spend my days maintaining a few years of data at work. Making sure it's backed up, always accessible.

I do not want to do that in my off time.

I know "do it locally" is often repeated here, but do you really expect a local solution to be able to get this kind of information and keep it safe, secure, and constantly working for this long? And how much time, money, and effort should you spend maintaining such a solution?

I have data in my Google account going back 10 years! That's impressive as hell!