It appears that some features, like real voice recognition/analysis, accents and the ability to impersonate others, are features that can be turned on or off.
After several tests, I’m convinced that the advanced voice model cannot actually hear my voice, but I’ve seen demos from others where it’s suggestive that it can. I say suggestive because the model can actually lie at times and make educated guesses based on what it knows about you.
I’m not sure why some people are getting the fuller featured version, but it could be regionally based.