There’s a theory that says this is the case (I can’t remember the name) but if it was accurate it’s probably been thoroughly destroyed by the modern diet which is laden with foods that push reward cravings (like excessive carbohydrates)
You’re both wrong for speaking in absolutes. It could be pica but it’s impossible to fully assess such a situation based on a literal sentence description, you would need to know the context, frequency of behavior, occurrence with other items (eg is it solely soil). It could be soil eaten out of desperation to alleviate symptoms related to iron deficiency but again, impossible to know from a single sentence but a child eating soil would be grounds to evaluate for pica unless the child was specifically instructed or something (eg folk medicine)
brought to you by someone who spent 5 years doing neurodevelopmental evals of autism and intellectual disability in children, where pica came up a decent amount of the time (especially for the kids with ID)