Since how I'm describing things seems to be ringing at least partially true to you, I feel like that kind of reinforces my point, because I would absolutely not say that I have aphantasia. I think we may be having very similar experiences, and we're just finding very different ways to describe it because the right words to describe it don't really exist, at least not in English at the level we're able to converse at (maybe there are better words that are in common use in psychological or neurological circles, but to most of us would just be meaningless jargon.)

The inner TV thing is not a bad way of putting how I experience it(personally I tend to think of it as more of a 3d animation program, because I have far more freedom to move things around, change "camera" angles, sizes, shapes, etc.) but it's also not not totally accurate to what I experience either. I could describe it as a full-on audio, video, smell, taste, touch, temperature, etc. experience happenening in my head, but it's also different sort of experience than actually experiencing those sensory inputs in the real world. It happens in parallel to my real world experience, and is equivalent, occasionally even overlaps with it, but is still a separate and different experience.

I think of it sort of like how hot (temperature) food and hot (spicy) food activate very similar sorts of pain receptors in your brain but are still very distinct sensations. I'm pretty confident that if you found people who have absolutely no experience or knowledge of hot peppers and fed them a habanero, then asked them to describe the sensation of eating it, that most of them would probably come up with descriptors like "hot" or "burning," and we can all understand that, there is something in common between those two sensations that is hard to describe, but they're not exactly the same, you're not going to eat a ghost pepper and think that your tongue is actually on fire.

For me, the relationship between visualizing something in your mind and actually seeing something with your eyes is a lot like that, and probably even more similar.

And if someone lands on different words to describe spicy food, like maybe "tingling" or "itching" they're not wrong, even if we disagree with their word choice, nor are they experiencing something totally different than we are, their personal experiences have just led them to choosing different words to describe the same thing. What I'm describing as seeing or visualizing, or as an inner TV or 3D modeling program, you might might be experiencing the exact same thing but finding different words to describe, and we're both using our words in ways that don't make sense to each other.

There may also be sort of a skill component, some people have a knack for visualizing, and others have to actually develop that skill in some way, and maybe not everyone has the right opportunities or desire/motivation to develop that skill. You say you've somehow built yourself up from a 0 to a 2, so who's to say you haven't been doing it sort of subconsciously your whole life and you've just grown to have more conscious control and/or awareness of it? And maybe with the right training (and I don't know what sort of training that would be) you could continue to develop that.

And even with that increased skill, you may still find different words to describe how you're experiencing it.