Not OP, but, the troubling parts for me are 1) the tone of the post, and 2) the larger-than-SO issue of the gap in understanding copy+paste for the average user.
1) The post says "unfortunately" they cannot tie logged-out users to their logged-in account. In no moral way is this a reasonable perspective to me. It is extremely fortunate that SO does not build the tech to track you as a logged-in user when you are logged out. That's a bad precedent to set. Sure, some sites do that, but I think they shouldn't.
Other examples of the tone in the article abound. It's troubling for sure.
2) It is up to the web devs themselves to decide what goes in your clipboard. Many users don't know this. Sites that exploit the gap between user expectation of privacy while copy+paste as well as tracking do not match with reality. Stack Overflow is merely one of many players here, but they way they exploit this gap is mildly upsetting.
Something needs to be done, either technically or communication to users, about copy+paste reality.