Recycled plastic is plastic, probably thermo plastic that is temperature sensitive. The plastic lacks hardness and is therefore subject to deformation under load. The plastic, lacking compressive strength, will deform
Deformation means that after a short interval the heated roadway will change shape under the load imparted by vehicle wheels. It will be rutted in short order.
Shitholes gonna shithole.
Asphalt deforms too — which is better than cracking. They are able to reuse old asphalt, by adding the recycled plastic. It gets rid of plastic, greatly reduces asphalt waste, saves money, and results in a better road surface. A win all around. It just looks like good engineering to me.