I am on the side that this isn’t semantics and is a real phenomenon. For me, I can hear in my mind very well. I can hear so well that I can occasionally confuse things I’ve hear in my mind’s ear for a real sound (did you just say something?). It very slightly crosses the line into an auditory hallucination. I can hear music so well that I don’t need a radio to listen, just think of the first few seconds of a song and off it goes on the jukebox.
My mental images are nowhere near this clear, but they are a kind of “darksight” a seeing and a not seeing, ephemeral but also real and useful for visualization and problem solving.
I can relate. I'll also get songs viscerally stuck in my head that will play nonstop for several days straight. And not only music, I'll occasionally get stuck images as well, pictures that will sit in my peripheral thoughts for days.
My mental images are nowhere near this clear, but they are a kind of “darksight” a seeing and a not seeing, ephemeral but also real and useful for visualization and problem solving.