[pathdependent]

Full quote, for context:

   Being conservative, let’s say it makes you 5% more productive.

It's subjective. I'd like to see a before and after study, but empirically measuring code productivity is -- a hard problem.

[IshKebab]

It might no be too hard in this case, since you're really testing editing speed not code productivity. You could take a random selection of (small) git commits and time how long it takes people to recreate them. That maybe gives Vim an unfair advantage actually since the IDE features help more while actually composing code, rather than just editing text.

Still I think it could be measured.

[Veen]

I think the focus on speed is counterproductive. Increased productivity isn't the only — or even the most important — measure of value.

I enjoy using Vim (Emacs Evil mode these days) because I can edit more fluidly without having to shift focus and context switch. My hands stay on the keyboard, my eyes stay on the screen, and I don't have to think about "how" to achieve my goals — I just think about what I want to achieve and muscle memory takes care of the rest.

I might edit more quickly, but that's a side effect of using a tool that allows me to focus deeply and maintain that focus for longer: both of which are vital to flow and satisfaction with my work.