Fortunately those are not the only two options.

Right, just look at our local playgrounds: no more wood anywhere in sight, just faux-wood plastic that never rots but just slowly sheds microplastics into the environment

I'd be less concerned about that than the fact that every car that drives by the playground is shedding pounds of tyre plastic into the air/water as a matter of course. At least the playground materials aren't designed to turn into particulates.

So true.. plus all the "plush" plastic pellet "landings" rather than simply dirt cause oh no: someone may get into contact with some microbes.. gotta keep those allergy numbers rolling. /s

That's a false dichotomy and I'm sure you can do better.

As a parent you just spend a minute or two inspecting a playground. It's easy to spot something that is rotting.