@trwnh oh, totally. To be clear, the way I imagine it is that to end users, it all looks like a single identity, and which feed/stream is negotiated based on the context you're using the identity. So, e.g., my main public profile might be "blaine@bcook.ca", and if someone tried to follow me on mastodon, they'd get my "short text notes" stream, and if someone else tried to follow me from pixelfed they'd get my "square format insta-like-social photos" stream.
@trwnh I'm doing some extreme handwaving over content negotiation and defaults and all of that, but maybe one interesting thing to raise at this point is that once we get here, "blaine@bcookc.ca" isn't a mastodon account – it's me, a person, with all the facets that I want to share with people who have that name to call me by.
It also means that I bring my identity with me into different social contexts, and that means trust, too. And links to other parts of me, etc.