Yep.
If people would quit fixating on making an AR-15, they could make many quality guns with nothing more than a simple lathe. If they’re willing to invest a fair bit of time, they could make a passable gun with a drill press and a bunch of hand files.
If people get off their plush posteriors and started reading (there’s that word again) about older single-shot guns from the 1880’s to 1900 or so, they’d find that there were many falling/rolling block designs one can make pretty easily without much in the way of machine tooling. All you’d really need to buy would be a barrel. You’ll need to buy a chamber reamer, but you can ream a chamber by hand, you can make all the cuts needed by hand, and if you clamp rather than thread the barrel into the receiver, you might not even need a lathe.
Been there, done that.
“Mr. Single Shot’s Book of Rifle Plans — designed for the serious gunbuilding enthusiast. Included are detailed instructions on how to build four unique breech loading single shot rifles, from metal stock to a finished rifle.”