MonadFail instance for Either

[Daniel Bergey]

Is there still consensus in favor of adding this instance?

 instance IsString str => MonadFail (Either str) where
    fail = Left . fromString

In 2016 there was some discussion, and my reading is that there was consensus in favor at the time:
Trac: https://ghc.haskell.org/trac/ghc/ticket/12160
libaries mailing list: https://mail.haskell.org/pipermail/libraries/2016-August/027248.html

Does anyone know of a later decision not to add it, or was it simply no one's top priority?

What is the next step to move this proposal forward?  Is more discussion in order?  Should I just submit a patch?

Thanks,
bergey