Exactly. The author tries to present as valid his his agenda of "optimizing everything" when he's actually optimizing for a desktop Chrome browser on a fast computer.

Written from a ten year old notebook. Progressive JPEGs are slower for me no matter which browser. Not having Chrome browser on the newest computer? Still slower. Mobile devices: the same story.

If the author never leaves his desk, has a new computer and likes Chrome browser, good for him. Others shouldn't trust him too much.