Many people with aphantasia are unaware of it because they can function just fine and have workarounds that fills almost all their needs. They simply cannot add an image to it.

Personally, I can make memory palace work fine. There's simply no image, so it rely a lot on the same "path finding" the brain uses to allow me to walk around town without getting lost. I like to joke that my GPU is broken but my CPU works fine.

So, for the sake of etymology I guess it would not be visualise but factualize or some other word.