Note the wording "we reasonably believe". There is nothing objective about this.

Additionally: https://policies.google.com/terms#toc-removing

> Removing your content

> If any of your content (1) breaches these terms, service-specific additional terms or policies, (2) violates applicable law, or (3) could harm our users, third parties, or Google, then we reserve the right to take down some or all of that content in accordance with applicable law.

Finally, buried 3 links deep in the Terms[0], we can find a list of some of what Google considers valid under this clause. A lot of it makes sense (clearly illegal things) some of it is subjective ("misleading content"). If you feel comfortable all of your data could never be interpreted by anyone as falling under any of these categories, be my guest, use GDrive.

[0]: https://support.google.com/docs/answer/148505