Technically this wasn't caused by those instructions but by the spinlocks waiting for the lock to be released. Also "blocked by seven instructions" sounds a bit click-baity.. you can lock the CPU or power off the computer with less than that amount of instructions :-)
Did you read the post? There were no spin locks waiting for the lock to be released. The ~100 threads waiting for the lock were all waiting in an idle state, quite efficiently.
The problem was that the thread that owned the lock was spinning in a seven-instruction loop.
I think the point is that you have this beast of a computer and the lions share if its power is going to these 7 instructions. It's a bit theatrical way of putting it, but in the article he doesn't actually blame the 7 instructions for the root problem.
