My issue is with glass smashing into pieces under the smallest falls
Plastic is easy to scratch. Glass is much stronger and can withstand a lot higher forces then plastic without scratching or breaking the screen under it.
Hard to break isn’t the only thing you have to take into consideration. You want the material to be scratch proof or scratch resistant as well. The best material that is really hard to break and hard to scratch is glass, or whichever gorilla glass version they use in phones currently; plus it’s thin enough and much more responsive.
Some foldables use plastic screens
But it is really not making the screen as durable as one would think
They used to be.
They’d scratch when you even looked at them funny. Moving to glass was a huge advancement in the field. Heck, we’ve moved to the backs of phones being made of glass rather than plastic or metal a lot of the time because we all just hate scratches.
Plastic easily scratches. You can have a screen that scratches easily but doesn’t shatter, or a screen that shatters easily but doesn’t scratch; but you can’t have a screen that neither scratches nor shatters.