> So you're both [edit: all] saying that Congress is being paid (by who? UPS/Fedex?) to screw USPS over.
I don't see anyone saying that Congress is being paid to do that. Congress has lots of members who favor privatization of government services in general and the post office in particular, but outright privatization seemed like it would have a political cost that they weren't willing to bear. So they put in that measure, with the intent of building political support for privatization over time.
Whether the preference for privatization is honest ideology, corruption, or something else is its own issue.
> Why wasn't this mentioned in the article if it's such a well-known scheme?
The article mentions the mandate as one of the central problems facing the USPS, and the fact that it is a requirement that neither private businesses nor other public institutions face.