The fun thing is this is a designed fabric. There are very few other designed materials designed in this way. Kevlar, nylon and those such things come to mind

The fun thing is this is a designed fabric. There are very few other designed materials designed in this way. Kevlar, nylon and those such things come to mind as designed from chemistry up - miracles of the chemistry of the '50s & 60s. This is different in that the design is done using a much more standardized and modifiable plan - genetics. A huge difference, is these fabrics are protein based, and as such, can have productive & useful variants made simply by changing the genetic code from which they were produced; monumentally easier than researching nylon into kevlar, chemically. This is an entirely different R&D schedule. And the bounds are what can be found in nature. It's not so much that they can produce spider silk, but that they can relatively intelligently direct their efforts to produce spider silk that also does <insert biological property here>.