Comment by importantbrian

I'm not sure this is a great example. A formula 1 car is significantly larger and more complex than any go-kart is is 4-5x as fast. In fact almost any car you can purchase will significantly out perform a go-kart.

I don't think just adding features means software must be slower. I would venture to guess Emacs has more features that Word, especially when you factor in plugins, and is significantly faster than Word.