Cognitive empathy requires not a face, not preferences and demographics, but the underlying reasoning, reactions, and guiding principles.
Describing Personas
Indi Young

Won’t people naturally tend to visualize a specific physical likeness after reading a descriptive persona (we do this every time we read fiction) — and then just make assumptions based on their internal image, as opposed to one codified in a persona?

It’s REALLY hard to remove assumptions from the human thought process. They’re an extension of basic survival instincts.