The moola-avidya people hold that avidya-sakti is a powerful primitive force, a force that prevents us from realising our true nature as existence//consciousness/bliss. Opposed to them are advaitins of the school that maintain that avidya is another name for superimposition. This is a simple characterisation of the divergence of views but I think it is fair to say that understanding ignorance as a force or a real existent arises from moving from an analogy i.e. ‘like a cloud’ to a metaphor,‘is a cloud’ . It may be just that simple.
Ignorance essentially is a non-cognitive relationship. We may know in general what the outlines of a topic are but the core of it is opaque to us. It also is the case that we may be in a state of complete ignorance in the case of the unknown unknown or the perfectly camouflaged. It just isn’t there for us. I would suggest that avidya/adhyasa is more like the known unknown that can be pointed to via the finger-post of a transcendental postulate. Start from the hard question - how is consciousness possible? On the face of it it ought to be impossible and there are various arguments for this ranging from causal closure to the gulf between the extended and the non-extended or cerebral events and qualia. Yet it happens. Here the outlines of a known unknown begin to become clear. We are at the start of atma-vichara or sefl-inquiry.