For one thing, “ideology” is a twentieth century word. It is practically made up, whole cloth. So, that’s suspicious.
Surely, though, the forms and functions of ideology isn’t restricted to a single century or one type of thinking. Within the twentieth century alone, by way of the briefest survey, one discovers a range of usages and applications. The journalist, Hannah Arendt, tended to use the word one way, with her references to and descriptions of large movements and political propaganda. The essayist, Christopher Hitchens, never used the word at all, as far as I can find, though he wrote extensively about explicitly ideological themes. Proponents of the Continental schools of philosophy use the word in a very different and narrowly technical way, compared to common usage, which strips away superfluous synonyms.
Here is what happens when the topic of ideology is breached. The word splashes into a conversation like a dead fish on a finely set dinner table. The first thing people seem cued to reply with is East Germany, or themes like that: of Gulags, concentration camps, hippie communes and varied pathological cults.
I think that ideology, as such, is quite a different thing — those other examples being, instead, samples of “enthusiasms”, “obsessions” or “propaganda”, but not of “ideology” proper. And anyway, a focused discussion about “ideology” inspires either glazed-eyed boredom or nervous laughter. It is too obscure on an everyday level, and it’s terrifying in turns. I shouldn’t blame anyone for fleeing from the zeitgeist. Does anyone really want to get involved in talking about that aspect of human behavior which is the least tractable in common experience and which would serve as definitive proof that Free Will doesn’t exist? I’m thinking, “no”.