We have tons of second hand plastic toys. We generally only buy consignment toys. So, I feel better about "recycling" the plastic toys by using them, instead of them ending up in landfill. But the 'wooden/natural' products are more basic, simplistic, ambiguous and provide more creative multi-use due to their ambiguity. A generic "vehicle" could be an ambulance, car, van, truck, firetruck, bulldozer, etc. The child's imagination provides the imagery. A wooden building could be an office building, a school, a hospital, a store, a home, etc. Same with a generic four-legged animal. A cloth doll with no painted on "happy" expression could be a baby, a doctor, a mama, a sister, a friend, a teacher, a princess, a fairy, an angel, etc. The doll can have emotions (happy, mad, sad, sleepy, laughing, etc.) projected from the child's imagination instead of directed by the manufacture.
Surrounding a child with natural materials introduces them to things of beauty from nature that have the visual, textural quality retained and/or crafted into them. Rather than manufactured by machines from artificial materials with toxic colors and chemicals. But natural materials means that part of nature was used/removed/destroyed to produce them too.

So, I guess it depends upon your and your child's priorities. We introduced plastic before I had been introduced to the benefits of wood. We have both. The other plus of natural products is that they are generally child "motorized", rather than battery operated. (Which adds many used batteries to the environment.) Child activated toys provide more interactive potential. But I have seen ds utilize plastic toys in his own creative ways. So, the utility value of any toy resides in the imagination of the child.
Pat
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