They gave some coreboot devs laptops but didnt invest anything apart from that, afaik. The result was not working well enough, so they use insyde (which has pretty cool features but also past security vulnerabilities and it is backdoored by Intel & the NSA)
Like, UEFI being backdoored by the NSA is not a conspiracy. “Persistence” in “end user device data retrieval” was one big goal. Persistence means than an OS reinstall, Secureboot, boot integrity, QubesOS disposable Cubes etc. will all not protect you, as that shit is in the firmware!
No security or privacy without coreboot. Google knows that and has all their servers on coreboot and also all Chromebooks. Android is ARM so that is different but also WORLDS more secure than any secureboot garbage.