AP has turned a corner. It's standardized and in wide use.
Building extensions on top of AP is useful and necessary, but starting over with incompatible protocols is a bad plan.
Blue Sky in particular is a bad project. It started after AP was standardized. The team had access to many many people's time and all the docs and experience of the fediverse.
But they opted to make a snowflake protocol instead. I think because they want to capture value at the protocol level.
Don't use Blue Sky.