Plastic is defined by its moldability. Thus, plastic is like the software of the manufacturing world. It allows humans to think up ingenious uses for it, and this makes it interesting to think about, and so more products are thought up and the cycle repeats.
Plastic is almost infinitely moldable.
Contrast this with wood. Wood has a grain that reduces the number of ways you can do things. It also takes dozens of years to grow a tree. You don't have to grow it, log it, seed it or truck it. It is also remarkably pure.