I think in the first two examples in the linked warning you have daylight in making that argument. Both of those examples of the use of “stupidity” could have gone the other way, though. But in the case of TDS, in the context of your post, it was a bridge too far to construe it the way you are saying.
(my bold in each of the above).
**Entertainment Weekly: **The Flash is a better show than Arrow!
**Person 1: **I agree, I really think The Flash is a better show than Arrow.
Person 2: Anyone who thinks that The Flash is a better show than Arrow is stupid.
Your take is that Person 2 isn’t insulting Person 1? I disagree. This could easily be avoided by being clear on who you are trying to disparage. Maybe, ‘Entertainment Weekly is stupid’.