Does "recyling" include paying Chinese "recyclers" to take it? Because if so then I don't think it's actually being recycled.

What, pray tell, are they doing with this low-grade recycled plastic? Putting park benches out into the environment that will degrade faster, distributing microplastics everywhere?

Or are they investing a ton of time and energy to recycle the plastic into higher use (than park benches), which likely has significant input energy costs, which in turn is probably harming the environment?

You can't get anything for free, and recycling plastics least of all. The most environmentally friendly solution I'm aware of today is to simply relocate it all into one contained location and incinerating it as cleanly as possible or burying it in a landfill with protective sheeting. We're not even close to running out of landfill acreage on this planet.