I’m not sure how familiar people around here are with Zelda Classic, but Zelda Classic started as a engine reimplementation of the original The Legend of Zelda on the NES, making it run on MS-DOS and later on Windows PCs. The unique thing with Zelda Classic is its level editor, making it possible for users to create entirely original quests, with the best custom made quest maybe even rival the old Zelda games made by Nintendo themselves.
A couple of years ago Zelda Classic moved its codebase to GitHub, going open source and all that.
The benefits of a libretro port of Zelda Classic compared to just using the various versions found on the web could be many, one being having the clean RetroArch frontend with full controller support instead of having to fiddle with gamepad wrappers such as Xinput Plus just to get a modern Xbox One gamepad to work with Zelda Classic for the end user (been there, done that).
An other benefit could be to have the ability to within the core options itself to have custom configs for each custom quests, and thereby selecting which version of Zelda Classic to use based on the custom quest (running a ZC 2.10 quest in ZC 2.5 may cause issues in terms of both gameplay- and completing the actual quest).
I have no idea whatsoever how much work this would be to port over to libretro, how popular Zelda Classic is nowadays (something tells me it peaked 10 years ago), if this could end up as a niche that only few people care about and so on.
The only thing I can add, is that if this somehow in the future happened, it would be cool.