Hello,

I believe this bug is due to a change in emacs to where the tramp-default-remote-path was moved from tramp-sh.el to tramp.el: https://git.savannah.gnu.org/cgit/emacs.git/commit/?id=695f6792f1524a446d276bf5c5e53bbb4c200909

Due to this the source snippet in emacs that adds guix paths did not work, as you should see by examining the variable: C-h v tramp-remote-path

I've tested this patch builds, sets tramp-remote-path, and alleviates the sudo problem I also experienced (for local tramp). Please test if this fixes it for you. And maybe someone can relay this to the guix-devel thread mentioned in case there is more to be done as per the discussion there.

Thanks,
John