It's a single anecdote that deleting Chrome on two computers sped them up. It provides zero evidence (even anecdotal) that it has anything to do with "Keystone" specifically. It provides zero evidence for the idea that "Keystone" is able to "nefariously hide itself from Activity Monitor". And it also completely contradicts the normal user experience of Chrome, which is that most people's computers don't slow down after a Chrome install. (WindowServer on my MBP usually uses <10% CPU and I've used Chrome for many, many years.)
Why is this nonsense being upvoted? I get people dislike Google and Chrome, but wouldn't it be better to stick to things backed by real evidence?