Yes, bioplastic can replace petrochemical products, provided a more efficient way to produce bioplastic be created. The only hurdle standing in the way is easy of production, and given the drive to do so, I have little doubt that the scientific community could come up with one. Then, bioplastic would reign supreme.
Petrochemical products should be replaced with bioplastic products because the latter is more organic and biodegradeably harmless to the earth. This could conserve remaining fossil fuels and prevent pollution leading to a healthier planet. Petrochemicals use remaining fossil fuels as well as being harsher on the environment, preventing from using the products can also be beneficial to health.
The corn used for bioplastics could also be used to feed population in needed. You know that all the 3.6 seconds a person starve to death in the world ?!
Moreover the propreties of bioplastics still not mimic pretroleum usual plastic.
It cost a lot to make research and produce bioplastics !!