content: 3D Printers aren't new technology, they're more than 30 years old.  People that say the stupid unrealistic stuff probably don't know that, and expect rapid growth rather than the steady slow improvements we've been seeing over the decades.  The fact is, the only reason those people are even aware of 3D printing at all is because the technology is so old that the patents have expired, leaving the tech open for anybody to sell however they wish...  which leads to lots of crowd funding campaigns where crooks make up all kinds of nice sounding lies to try and get people to part with their money.