It’s much more efficient than other materials in many ways.
If every single-use plastic container/wrapper had to be replaced by some kind of paper or waxed paper doing the same job, we’d need dramatically more of that material than plastic (barring clever inventions).
That comes with its own side-effects. More dead trees if it’s paper vs plastic, more metal mining if it’s metal vs plastic, more weight being shipped around, in many cases more energy being used to produce the alternative packaging in the first place. And all that to have packaging that’s functionally worse than plastic.