This reminds me of that old site that made reddit look like Outlook so you can pretend to be working while on reddit. Now I'm pretending to be on reddit. The ol' switcharoo yadda yadda
An NNTP binding would be a bit more directly mappable, as Lemmy’s more analogous to Usenet than email. Each community would be a newsgroup. Still, NNTP and SMTP are pretty closely related, to the point that Outlook Express supported both email and Usenet. Subscribing, reading, posting, and commenting are pretty easy concepts to map, only up and downvoting are unsupported.