You've assembled guns, probably, from parts you purchased. Like Legos. I doubt very much that too many people are hammer-forging 7075 receivers in their garages...
Drawing back to the original point, who is building a drone, or anything. There is only one guy I know of (primitive technology on you tube), and the most advanced thing hes made is a hatchet and charcoal.
This is like saying you didn't make homemade bread if you didn't grow the wheat out back. It is a pointless statement countering an assertion no one asserted because the rest of us know that home made bread means from store bought ingredients unless specified otherwise.
This is actually my point. It didn't say "no one" is doing it. Even though his means are very crude, he still needs a furnace, a welder, and a lot of other tooling (receiver jig, etc.) to get to the point where he can use a bucket of pre-fab parts (most notably the barrel).
That guy is building a receiver, then assembling. Most people who are into it are just assembling.
This is like saying you didn't make homemade bread if you didn't grow the wheat out back. It is a pointless statement countering an assertion no one asserted because the rest of us know that home made bread means from store bought ingredients unless specified otherwise.