@are0h all of this, so very much. modular pluggable extensible services. flexible clients. data extraction and translation between stacks. none of this should be at all controversial and should absolutely be front of mind for folk interested in building the future of the fediverse imho.
there's no reason fedi servers cannot be set up to let you take your content with you and load it up somewhere else, and the good ones should even set up redirects for you if they're going to still be online. it's your identity, it's your content, you should be able to slide it around as smoothly as the underlying tech can support, and it can support so much more smoothness than it currently has, but the people interop side of the equation is the part key sections of the fediverse never seems to be ready for. maybe those sections just need to be left behind.