> It just puts Google in the same sandbox Google puts everyone else.
Yes, you can do that, but Graphene is probably best used without Google apps at all. If you use Google Maps, sandboxed or not, Google still knows where you are, what speed you drive, etc, and can rat you out to car insurance companies or the government.
Graphene OS devs themselves recommend that you install apps on Graphene OS via Google Play Store for security reasons. They also explicitly recommend Graphene OS users to not use F-Droid or Aurora Store. Make of that what you will.
Yes, you can do that, but Graphene is probably best used without Google apps at all.
That totally depends on your goals. For some it's security, for some it's privacy from Google, for some it's removing the ability from Google to (worst case) remote brick/block your device. The latter may sound a bit far fetched, but if I was employed by, say the ICJ, I would know what system I'd run to avoid that.
One of the things that I like about GrapheneOS is that it accommodates all these use cases and on a gradient (e.g. personally privacy from Google is also important, but I like that I can use sandboxed Google Play Services with most of its permissions removed).