It is too bad Google has fallen so deeply in such a short amount of time; they have depricated the Pixel sources, keeping security patches closed for so long, do not communicate properly and created a walled garden with Play integrity services rather than using the more universal and more secure hardware attenstation, excluding payments to Google-approved OS's only and locking out app developers from the Play Store unless they agree to Google's terms like an extortion.
The GrapheneOS team did such a great job to mitigate these issues so quickly and put so much extra effort into it, despite of having no Pixel sources, which his extremely resource-intensive and time-consuming, and giving people the alternative to make their own choice for timely security patches. And on top of that they made a fantastic deal with Motorola in order to resolve those issues. All in a day's work with such a small team of developers, I am super impressed by that!!
They made a great landing, despite of a seemingly impossible task. Hats off to you!