I don't see any reactions here that would justify you telling them to "chill out". They're stating their problem in hope to see if anyone else has it, and thus helping them determine if it is a problem unique to them or not. I really don't understand what you're getting at, are you suggesting people should just not bother complaining or talking about it? Because that is all that is happening here, people are talking about it. There is no overreaction or anything of the sort. How do you think Apple find out about these things? People talk about them!
However, I don't think it's wise for you to carry on downplaying this issue - yeah, he perhaps didn't pick the best screenshot to show the issue, but it an issue that requires significant attention because yes, it does effect how you use the system, text and menus become unreadable and almost unusable and videos are horribly broken by it.
When it occurs, that is.