Oh that is very interesting! I guess the main way that they decompose is through PHA depolymerase–according to ChatGPT a lot of the species that have been tested in the decomposition of PHA are bacteria. It would be interesting to try inoculating some samples of PHA with different mushroom species as well. It would be really great if PHA could be fully-decomposed into proper food-safe compost.
On the other hand, I have heard people ask that question, answered yes, and then checked my receipt later to find out that I just handed $0.57 to round out the cashier’s drawer.