The background story of the project is quite sad, so it sort of makes sense that he is very defensive of it. (The project got some monetary support initially from a company, which later tried to hijack the whole open-source project (going by copperhead os nowadays, I believe). Fortunately thanks to Micay the original was unharmed (he revoked private keys, big kudos!), but they do throw shade at GrapheneOS promoting their shady fork in many relevant threads)
Nonetheless, he is an excellent security researcher who has an excellent track record of prioritizing the security of his userbase, even if he may (more or less validly) be a bit overly defensive over it.