Pixel 8 and later have 7 years of support from launch and so does the Motorola Signature 27. It isn't GrapheneOS extending the life of the devices but rather GrapheneOS only using devices with long term security updates. We do greatly improve the security updates during the lifetime of the device but it stops being safe to use devices without firmware updates after end-of-life. Official GrapheneOS releases are for devices which aren't end-of-life. We provide extended support releases for devices past end-of-life as harm reduction, but we don't do it indefinitely. We've found providing extended support releases can be quite counterproductive since people won't listen to us and will continue using or even buying the devices despite growing insecurity. It's going to be a lot worse now with AI models able to help anyone develop exploits.