I think we basically agree, just using words differently.

Ideology is, in my usage, an identity. *"I am an X." X can be socialist, catholic, christian democrat, moderate, african, working class woman, flat-earther... Some are more fixed than others. But genrally, people make political decisions based on these political identities.

Your example is perfect. More or better facts will not change people's understanding of that politically charged fact. It will usually be a byproduct of their wider political identity... including ideological affiliation. Ideological affiliation is probably the most important form of identity.