Google's hardware is just hardware. It is not locked down like the hardware of many other manufacturers. Moreover, it's the only such hardware which also allows you, the user, to lock it down for your own security. GrapheneOS is not just focused around avoiding Google, it's more accurately focused around security and user choice.
The goal is to give you the option to avoid needing to rely on Google's spying or services while not having to compromise on security.
None of these other solutions regularly get included in Celebrite's documentation as being an explicit benchmark of their software's ability to break into phones. And that's almost certainly due to the fact that unless you leverage hardware security features like what GrapheneOS (and stock Android on a Pixel, and iOS on an iPhone) utilises, you have no chance of going against any actual adversaries.
And I'm not just talking about state actors here, even drive-by opportunistic attacks are likelier on a random other phone running some other Android build.
So yeah, you are running Google hardware, that doesn't make you "googled". It's just a sad reflection on the reality of the hardware landscape. If you want the same security as what GrapheneOS offers, you will currently need to use a Pixel.
I'd be curious to see what comes out of their Motorola partnership though.