So I opened somewhere around this moment: https://youtu.be/7Hlb8YX2-W8?t=17039
And, first, he copy-pastes some code, and then spends about a minute figuring if he got tabs converted to spaces, including googling a vim command.
Then he proceeds to make a loop over some collection next to the loop over an adjacent collection. And he makes that stupid mistake of renaming a variable of the loop, but no renaming in the body.
Man, if that's how professional vim users work, this piece of video will be the only proof I will ever need to prevent zealots from even wasting IDE users time to try vim.