Out With the Old

Look before you delete#

Open your init.lua and read it honestly. Most configs are three things wound together: settings you still want, keymaps you still want, and a plugin manager you have outgrown.

Only the third is going.

Remove the block#

Delete the Plug block from the first call plug#begin() to the last call plug#end(), plus any require('...') calls that only existed to configure those plugins.

Then clear the state so nothing is silently reused:

rm -rf ~/.local/share/nvim/site/autoload/plug.vim
rm -rf ~/.local/share/nvim/plugged

Your settings and keymaps survive untouched. That is the point of looking first.