Earlier quoted context omitted.
> They're not interested in the blobs, but in the people accessing them But if they don't know what the blobs are, how does this help them? What can they tie it to? The latitude and longitude coordinates of my current location have an sha1 hash of 0950e97d3a2e4839e39ad27deb2e852d498100ae. Is this useful information?
Don't you need a proprietary firebase SDK in your app to use it? Do you know what data are included in the requests? I would argue that anything as simple as IP + UA/OSidentifier can be of interest to Google
(This is my first time building anything that involves a "backend", so I am pretty new to this!)