To my understanding, it's the strip Rise of the Machines from Saturday Morning Breakfast Cereal, by Zach Weinersmith. Reportedly, it was "Posted October 2, 2018 at 11:08 am".
Due to the nature of that webcomic, it isn't quite a story, but a single, standalone comedic strip.
Added: As for the content of the strip, there isn't much more than the exposition of what you said. Here is a description/transcription.
A man and a woman dressed as guerrilla fighters stand atop a pile of damaged robots.
He:- That was surprisingly easy. How come the robotic uprising used spears and rocks instead of missiles and lasers?
She:- If you look at historical data, the vast majority of battle-winners used pre-modern weaponry.
Narrator:- Thanks to machine-learning algorithms, the robot apocalypse was short-lived.
Bonus panel: A robot says:- So many generals conduct land-wars in Asia. Must be a good move.
http://smbc-comics.com/comic/rise-of-the-machines