Not to mention you send anyone a gun without an ffl and it's on you as much as him.
I suppose that's technically true but generally not much to worry about unless the "smith" has been doing activities that have raised BATF suspicion. They do have a lot on their plate...
I ship and receive the occasional gun at my home - pre 1899 antiques as I do not have any sort of FFL.
Now, I've bought all sorts of antiques which are the very same model as those made after 1898 - think 1885s, Colts etc.
Under Xray (if they even bother doing that...) they are identical and the only thing differentiating them is the number stamped on them. Nothing else.
Never once in 30 years has any shipment of mine, in or out, been internally inspected or opened.
I have received packages with the bolt, butt plate and once even the muzzle sticking out of a poorly packaged shipment and that didn't even raise any further scrutiny!
The only loss was once I shipped an Enfield action to an FFL holding shop and it went missing in transit - last tracked to a depot in Colorado.
By the law, it is a firearm, right? Oooooh....scary...
Well, guess what the response was...
Absolutely nothing - zero shits given
So, I say leave it alone and let others decide their tolerance level
...I'd suggest you think about supporting actual gunmakers who are trying to elevate the craft.
So, in your opinion Renner isn't trying to "elevate the craft"?
Holding an FFL has zero correlation to the craft of gunsmithing.