Paper plates are bad because they fill up the landfill and because most paper plates also have toxic PFAS chemicals which can end up in food during use or when heating such as in a microwave.
The PFAS chemicals can end up in your body and stay there for years.
You cannot and should not oven a paper plate as using a paper plate in an oven can result in a fire as paper plates are combustible.
The temperature that a paper plate burns is 451 F.
A paper plate will catch fire in the oven as paper plates are flammable and will combust with the temperature of the oven.
Paper plates are also coated with an adhesive which also becomes hot when the paper plate becomes heated in the oven.
Paper plates also tend to absorb grease and other food particles that can also cause fires.
You can microwave paper plates but not use them in the oven or a toaster oven or air fryer.
Always use oven safe cookware that won't combust when heated in the oven.
The average temperature for paper to catch fire is around 451 degrees Fahrenheit.
Metal and other cast iron plates are oven safe and even Pyrex dishes but paper plate are not oven safe and should never be put in the oven.
Even when microwaving paper plates they can catch fire if they are microwaved too long so you must keep an eye on the paper plate in the microwave as well.