I'm old enough to remember how companies all tripped over themselves trying to help the government spy on their customers after 9/11. I assume that every company that I do business with has an open pipeline to the government feeding in all the data it has about me.

No, they can and will open your mail at will if they think something fishy is going on. USPS can’t open anything without a warrant.

My question was whether law enforcement typically requests the same data from private carriers that it does from USPS, not whether they open your mail.