well, that's what the end user sees, but we can't pretend to know what happens behind the scenes from a data perspective, and how that data might be used in the future.
> They require a court order to open your package and even then can’t charge anyone with possession.
this is not true. only first-class mail (13oz and under) is subject to any fourth amendment protections at all,[1] and your mail can be opened without warrant if it comes from overseas.[2] USPS can also x-ray and use other imaging techniques on whatever they want, they even describe it as a best practice.[3]
this isn't to say dead drops are a better idea; there are plenty of reasons not to go that route as well.
1. https://postalinspectors.uspis.gov/contactUs/faq.aspx
2. https://help.cbp.gov/app/answers/detail/a_id/114
3. https://about.usps.com/securing-the-mail/best-practices.htm