I'm aphantasic, and I'd say one advantage is that I'm not bothered by invasive vivid memories or anxiety inducing imagery. Just on a hunch, I think aphantasics are probably less likely to develop PTSD after trauma, as a big component of PTSD appears to be just this kind of pervasive, invasive and hyper-vivid memories. I sometimes feel that I'm missing out on something, but from experiences on psychedelics, which give me closed-eye visuals of geometric shapes and colors which don't go away until the effects pass, I think I prefer the still black void and relative mental silence (apart from the soundless inner monologue) of aphantasia to a 'richer' inner world that I'm not able to shut off. Would be happy to get other aphantasics' (as well as hyperphantasics at the other end of the spectrum) perspective on this
I'm curious what you mean by "soundless inner monologue"? I don't really experience much imagery at all but my inner monologue feels very close to how talking to myself aloud feels, so I wouldn't describe it as soundless. The verbal vividness of my internal monologue is actually how I imagined people with good imagery skills "see".
On the note of advantages, I know I have something weird going on with the back right of my brain specifically (focal slowing on EEG among other things), which I am pretty certain connects to my favoring of verbal over visual thinking. So I guess it depends on the cause of a case of aphantasia, but to me it feels a little like how blind people end up with heightened hearing. I think I've really developed strong verbal skills because of it, and there are definitely advantages to having strong verbal skills.
I recall a professor showing us a study once where students performed better on an exam when they were allowed/encouraged to talk out loud to themselves while they were taking it. He was encouraging us to talk through stuff with ourselves, but at first I found the result weird because I assumed everybody was always talking to themselves in their head. That was the first time it really dawned on me there may be large individual differences in how we experience thoughts.
Late response here, but hoping you might catch it!
I'm also very verbal, as that is the form most of my thinking takes. I do have some very limited visual imagination, but it takes the form of very vague and transparent 'flash' visions, and otherwise it's mostly a kind of spatial sense (I have pretty good spatial orientation, and it often surprises me how some people with vivid visual imaginations can be very easily spatially disoriented).
My inner monologue is running most of the time, and I tend to think in complete sentences, even stopping to rephrase when it doesn't make sense. But it's soundless, as in not being perceived as a sound. I'm a musician and songwriter, so I often sing and make melodies in my head, but these too aren't perceived as sound in any way resembling what I hear with my ears. Hearing your own voice all the time also sounds like an invasive and disturbing experience to me, but I guess everyone is used to their inner world. It seems aphantasia can be uni- or multimodal. I also can't imagine smells or tastes, beyond having a vague idea of whether a combination of flavours will be good. I have heard others describe tasting chocolate in their mouth when imagining it, and that's just not something I've experienced.
So yes, I'm also fascinated by the huge range of inner experiences people have, and how it affects their personality and relationship with the world