Rubber doesn't sound that important to me. The Wikipedia article includes all sorts of useful bits: it only went into European use in the late 1700s, at earliest, well after most datings of the Scientific and Industrial Revolutions; most rubber is now synthesized from petroleum; many uses of insulation like transoceanic telegraphs used gutta-percha which is similar but not the same as rubber (and was superior to rubber for a long time); and much use is for motor-vehicle tires, which while a key part of modern civilization, does not seem necessary for cheap long-distance transportation of either goods or humans (consider railroads).

So rubber doesn't look like a defeater. If it didn't exist, we'd have more expensive goods, we'd have considerably different transportation systems, but we'd still have modern science, we'd still have modern industry, we'd still have cheap consumer goods and international trade, and so on and so forth.