That's a very interesting topic. I am similar to @cAPSLOCK, so the topic is intriguing to me.
Interestingly, I don't feel any deficiency at all (don't miss it) and to me it helped to study some abstract concepts without a need for visualization.

The absence of the "mind's eye" in a small % of individuals is called 'aphantasia' and it first came to focus as late as 2015 when one of the first serious research paper was published on it (initially it was described as early as 1880).
https://en.wikipedia.org/wiki/Aphantasia


In short; if someone asks to imagine an apple with closed eyes, some people see a nice jucy apple, colored and everything, some see a sketch and some "see" nothing. The vision was fine in all tested individuals.

True "aphantasics" are close to 2-4 % of the population (depending on the extent of it, maybe just 1% for full aphantasics) and yes, they sometimes don't "see" dreams as well, but not in all cases.

AI:
Sometimes, I think that this is a protective brain property...for example if the brain "sees" some nightmares, perhaps shutting down the "mind's eye" is a way to escape this.

I had a friend in grad school who was an exact opposite-he had hyperphantasia and said that he basically had two full life's: one during the day time and another during sleep where he had adventures every night with color, interesting themes, etc, like a movie. I was a bit jealous about this aspect of it as I typically don't recall dreams, with a few interesting exceptions.

That's funny, because when i try to "build" a inner vision of a close individual, they are always looking like comic representations, with constantly morphing faces, in dim light, very 2D, like printed on cardboard. They never look like they'd look to my eye IRL. But i had the ability to remember everything i had ever read under hyperfocus. I lost that, though, while psychologists say my aging brain needs mostly all the power to stay "high functioning", and it also quite feels that way.