But its trivial to buy 20 pieces of aluminum tubes online? There are so many providers in most nations, that sell all kinds of shapes of all kinds metals. What am I missing?

He is entirely right. I often want short bits and the precut short lengths on Amazon are often the lowest friction. But when I need 4 feet I often just give up! Good luck to him

This is cool and all, but every manufacturing plant in existence has these problems and has developed tools to speed it up. Everyone has something special that doesn't fit just right, or has an infinite number of combinations to solve for.

This seems more like a free-market problem where there just isn't any incentive to capture a market below a minimum.

Interesting, but I got to this:

"Pricing cut-to-length tube is not "price per pound times pounds." It's a one-dimensional bin packing problem, and the details are where the money hides."

which is one of the a peak LLM sentence. ug.

Seems inspired by https://noxmetals.co/quote which is great. We need plenty more suppliers like this around the US.