My understanding following Cody Wilson's lawsuit to publish gun plans online, which is a more recent case, did not follow that. He ended up having to follow ITAR export compliance, although he was allowed unlimited distribution to US nationals and granted an ITAR license that might let him export under the conditions of that license.

  On remand to the district court, and on the eve of changes to the federal export regulations, the U.S. State Department offered to settle the case, and on July 27, 2018, Defense Distributed accepted a license to publish its files along with a sum of almost $40,000.[6][7]

Nowadays you'll find most gun plans end up on odyssee or surreptitiously on github or something like that. If you go to high-profile 3d gun websites they will almost always point you to a decentralized server that the government can't go after.

It seems maybe they might allow you to export it, but you'd have to get a license first, even if they were required to issue it to you could take years of lawsuits that a youtuber probably will not pursue?

https://en.wikipedia.org/wiki/Defense_Distributed_v._United_...