What most want is to not be reposted and ratio'd by terminally online people like Blue MAGA did on Bluesky. They also just want to post to their followers or friends, not the world.
This is the tip of the iceberg of boring questions that fall out, all of which have annoying user experience implications which are intimately tied to the underlying infrastructure and cryptosystems, effectively setting them in stone. There are reasons these systems fall into the camps of either federated with strong ID or really very centralized.
A core principle of ATProto is that the cost of switching is low, thereby facilitating real competition on social media. So the answer is two parts
1. App views decide permission parameters for their modality and frame the user experience
2. Users use these permission parameters to dial in their personal or community experience
I believe there is more middle ground than you leave space for. See systems like ReBAC/Zanzibar, Anonymous Credentials, and UCANN. Google Workspace is a good model that many many people understand and are happy with (IAM wise).
With a design like this, you can build an enforceable world-read, mutual-following-write version of Bluesky, something users ask for every time Bluesky announces any new feature.