You can microwave paper plates as long as you don't microwave the paper plates too long.
I've microwaved food on paper plates before and it's never burned the paper plate as long as I don't microwave the paper plates longer than a couple of minutes.
If you microwave the paper plates longer than a couple minutes then the paper plate could burn.
But microwaving the paper plates for less than a couple of minutes should be just fine.
Even foam plates can be microwaved for a minute but not longer than that as the microwave can melt the foam plates.
Plastic plates that are disposable plastic plates can also be microwaved for a few minutes and they should not melt.