Graphene has a lively and accessible discussion forum of its own, and another on Reddit. Unfortunately it’s managed, and somewhat populated, by a community whose rudeness and arrogance is notable even in the weird world of niche open-source projects. It’s not unheard of for the moderators to delete posts that are critical of Graphene, or ban users who post such things.
This is what I love about GrapheneOS. They are not afraid to call Murena and e/OS on their proven false claims about security and privacy. Do some research and you will find that e/OS, same as iodè, are phoning Google from boot. Additionally, Murena is on the take by the French government, which happens to be the most advanced EU country in terms of authoritarian behavior today.
LineageOS would be a way better option to keep private if you don't have/won't buy a Pixel phone, otherwise, and with a proven record, GrapheneOS is the only option out there.
Yes, the community is blunt, specially when they are being dragged through the mud by scammers like Murena. But look everywhere, you will not find a mobile OS that even comes close to the security and level of ownership of your device that GOS offers.