There is something of a paradox at work here. I do think the harder one holds to an ideology the more they tend to be rigid, arrogant, and unmoving. Sometimes a label can’t be avoided simply because the shoe fits. We’ve all had debates with creationists before, and most of us have come away wishing we could have the hours spent in those arguments back.
I can see how the article would read like “an ideology against ideologies.” The author I quote in the piece, Jason Stanley, agrees with you that there are mild or relatively harmless ideologies. While I’m willing to concede the possibility, I can only imagine these being systems of thought about relatively meaningless or unimportant things. These would likely have some psychological significance to the person holding them, but I’m not sure much of a movement could be built around them.
Likewise, he [Stanley] feels that there are ideologies that people hold to only casually. I guess I would ask in response how loose a person’s grasp on a system can be before it stops functioning as an ideology? I take the position that if a person moves in and out of a system of thought relatively easily, without experiencing considerable cognitive dissonance or anxiety, it really isn’t functioning as an ideology in their life. It’s just a mind hack or perhaps an explanation they employ here and there out of convenience more than conviction.