I totally agree. The first Samsung s20 FE that came out I got it as soon as I could and I kept that phone for 3 years. (A record for me)I'm actually 100% in on this. This whole "premium" this is a cash cow. I loved the phones from 10 years ago that were plastic.
It had a glasstic back. Aluminum frame. It had a flat 6.5" screen. It was super light and durable. I never got scratches on the plastic back. To me, the Aluminum and plastic was a better combo than glass because I didn't worry it would shatter and it was lighter so dropping it in the first place was less likely.
From an Environmental standpoint I like glass or ceramic but from a purely functional and cost perspective I actually prefer the plastic. The glasstic also had a really cool almost pearl finish.
In terms of premium material beyond durability I could care less. However I didn't like the plastic frame and back phones we had like the Samsung Galaxy S4. It had that chrome plated plastic that would peel off. Just awful and super cheap.