You can choose to flip off people's qualifications if you want.... but it doesn't make what they say wrong, no matter hooooooowwwww much you don't like it. :)
Copying itself is odd and probably suboptimal behavior, but it is explainable without assuming malice: my guess is that it’s related to some kind of “before we update let’s update the updater” bootstrapping logic. I could be wrong, but IIRC the updater code is open source, so it should be easy to find out.
[Edit: Oops, it's actually not open source. Their Windows updater (Omaha) is open source, but their Mac one (Keystone) is not. Of course, one can still open the binaries in a decompiler.]
Regardless, moving a program around on disk, or even deleting the program while it’s running (which is possible on macOS), would not prevent it from showing up in Activity Monitor.
[1] http://www.reecefowell.com/2012/11/16/ksfetch-annoyance-on-m...
However, it happens (happened) specifically, if network access has been denied and there couldn't have been an upadate possibly received.
This user says their WindowServer runs hot. Some Chrome-related software may have entered a state where it accidentally DoS'es the WindowServer either due to a bug in google software or a bug in WindowServer that google software triggers, at least in the system configurations particular to this user.
I had my own run in with chrome recently where dwm.exe (Desktop Windows Manager on win10) would eat and eat memory until everything OOM'ed. Didn't use much CPU tho. I eventually tracked it down to a single chrome tab that had a specific website open. It's reproducible at least on my system but I haven't yet had the time to look into it more thoroughly. If I had to guess, it was the website making Chrome use some "hardware layers/surfaces" or something like that and cause the corresponding buffers in dwm to be retained forever. No idea if it's a chrome bug or a dwm bug or even some kind of driver bug, and just closing the tab was enough as a "quick fix".
For those that didn't measure, it's almost irrelevant — I'm telling you it's not a subtle difference. It's night-and-day.
It's very low on my list of plausible theories, but if there was a hypothetical keystone exploit, what is the latest on code-injecting WindowServer?
Also added an FAQ to the site: https://chromeisbad.com/#faq to address the low-hanging fruit of obvious objections to the possibility that Chrome/keystone is doing something to the system to cause it to thrash.
In fact, Un-googled Chromium (without the autoupdater) easily causes load that's displayed as WindowServer's, for me—when I open a Youtube video on my oldish Macbook with a shitty integrated video card. However there's little chance that I would think this to be caused by something else.
Even for malware, hiding from Activity Monitor would be quite a feat. Short of an exploit, you couldn't hide your process without a kernel rootkit, but macOS has required user approval to load kernel extensions for several versions now. I suppose you could go the low-tech way and just name your process "WindowServer" to confuse the user, but you'd still end up with two WindowServers.
The idea that Chrome's auto-updater is doing this is ludicrous.