With an average gunsmith, Most AR's are assembled, rifles are assembled or modified and fit. Very few rifles are built which I would consider taking various parts, in the raw or needing to be completely worked over every square inch, making many parts, and made into something that is one of a kind, very hard to duplicate, or a specific style to one person. Each part is fit by hand to minimal tolerances. I know of a few people that when you see one of their rifles, stocks, engraving etc, you can tell.... yeah that was done by so an so. The process of putting together a nice rifle isn't hard with the right parts, tools, know how, and attention to detail which is something that not everyone has. IMO the art of how well it was all executed is what sets different "builds" apart.
When I hear someone say they built an AR, I smile and say great, tell me what you did. They are happy as clams to tell you about it. Knowing that it takes very little skill, it makes them happy. While I build rifles for myself, it's always funny when I tell people first thing they say is "Like AR's and stuff", and I say, NO, rifles, target rifles for myself. When they realize I'm not a kitchen counter AR builder, The second question is usually "How do you rifle the barrels"............. on and on.....
IMO as Tacticool becomes more and more popular, and things like barrel nuts become more prevalent, the art of a True Gunsmith is slowly being lost. While it takes skill to produce record setting competition rifles, unless your name is on it, or it's your specific parts (receiver mainly), I couldn't tell you if you made it, I made it, or the kid down the street. Parts carefully fitted together.
Always strive to do better than the last.
To each their own.