Any sufficiently complicated Vim configuration contains an ad hoc, informally-specified, bug-ridden, slow implementation of half of Emacs.
There's quite a good chance that even the most complicated Neovim setup is faster than Emacs. Emacs lisp is notoriously slow, while Neovim uses LuaJIT, which is _very_ fast.
Not sure why performance matters in this case anyways though.
Obviously hard to compare because they don’t run the same packages but would still be interesting to see ballpark figures of setups with roughly equivalent functionality.