@adhdmarie
Based on the calckey alt I have on kitty.social, you can determine both original posts and boosts at different visibility levels, that should control for comments too for now. And for that instance (idk if this is *key-wide), there's a local-only option too. So there's public/unlisted/followers/local/direct mention. It's not quite mutuals but there's that.

I know bonfire is still in alpha but apparently quite stable, they do intend to have tiered access the way g+ had circles.
@franktaber @seachanger