And just as trustworthy as devices that are equivalent to desktop Hardware with UEFI, IntelME, etc.

So you mean like.....99% of all hardware in the world? Lol

If you're that hardcore into privacy or your threat model justifies it, then grapheneos isn't for you because you're already well prepared to make significant compromise and/or expense to pursue that goal.

GrapheneOS is more about leveling up more common people's privacy

Don't let perfection be the enemy of good