All the plastic phones I had were more durable than metal or glass. They scuff a little easier but plastic absorbs the hits rather than bending (metal) or cracking (glass).
Plastic is only unpopular for social reasons -- it is seen as less "premium." But aside from that it is basically the ideal material for phones, light, durable, allows wireless charging, allows signal penetration, etc.
Not to mention that it often comes with a grippy coating that prevents the phone from sliding out of your hand.
Oh, and not to mention the fact that everyone needs to put a plastic or rubber case on their metal or glass phone, so not only do people not get to see their "premium" materials on a day-to-day basis but also it's now significantly blown up in size.
I miss when they had a plastic removable back and battery - it would hit the ground and three pieces would go flying, but that's 3 different vectors for kinetic energy, instead of just one composed entirely of glass.
Plastic is only unpopular for social reasons -- it is seen as less "premium." But aside from that it is basically the ideal material for phones, light, durable, allows wireless charging, allows signal penetration, etc.