Stringed musical instruments today are better than the ones made even a few years ago. I'm not talking about the guitar one could buy at Wal-mart for $39.00, but the handcrafted instrument made by people who do it for the passion of it.
Technology isn't the reason, as the techniques used by custom builders hasn't changed much over the years. Sure factories have CNC machines to do carving and inlay and design, but the individual builder doesn't need or even want these machines. No, the reason that instruments are better now than before is the sharing of knowledge between builders. Almost all builders willingly share new ideas about sound production, about design, about a better way to attach this or that, etc, etc.
It is easier to get started building instruments now than ever, because the information on how to do it is readily available.
It's also harder to get started because the instruments must be just about perfect or they wont sell. They also must produce world class sound, and they must be artistically pleasing, or they wont sell. Buyers inspect instruments with little mirrors to inspect places not normally seen for a errant spot of glue, or a little stick not perfectly sanded. And they also bring magnifying glasses to inspect the joints with are perfect to the naked eye, but perhaps not perfect under magnification. All of this leads to instruments of really outstanding quality, and it makes the building of such worth doing.