It's a bit odd reading this because I learned just a few months ago, right here, that I am aphantastic (no mental imagery). Shortly after that, while discussing with some coworkers, I also learned I am anauralic (no inner voice). It appears they do sometimes go together: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8551557/ I think for those of us who don't have an inner voice, section "3.2 The Semantic Content View"…
[edit: Maybe "sublingual" isn't the correct term for what I'm describing. I remember reading about some MRI experiments where they asked people to "talk" without making any sound, and this activated the speech parts of the brain as if they were using motor function to speak. But I can't recall the term used for doing this.]