I have Samsung S25 Edge which is essentially same thickness (5.8mm) the biggest difference is weight, phone feels really light compared to my old phone.

The most annoying thing on the phone is wobbling when it is on flat surface thanks to lenses sticking out.

Battery life is alright. I can get 2-3 days of life from it with light use. If I am using it a little bit more, then it is barely one day of battery life.

And compared to iPhone Air it has real SIM slot.

Yep, weight matters a lot more.

For this they could engineer a good plastic but it wouldn't sell because it wouldn't feel "premium" enough. So instead, we get nonsense like that. And it suits them well because the thing is that much more likely to break so they get more chances to have the customer pay for repair or phone change.

Win-Win for them, lose-lose for the customer, basically everything Apple is about currently.