There isn't much of a debate about checking tracking with Tor. Even if we stupidly assume that they do not monitor for this, it only takes a basic level of tech education to realize how trivial it would be for them to check for this and flag all packages checked with Tor. Packages checked with Tor almost certainly contain contraband, and given how trivial it is to detect packages which have tracking checked with Tor, it is obviously a trivial system that would result in a high success rate.