First, I think that the chain looks like this: science produces theories/concepts/explanations/recipes, then engineering takes them and makes practical products on that basis, and then people use these products. So if science stalls, the pipeline will be empty and, basically, there will be nothing much for engineering to do except polish the existing products.

Second, looking at history is a bit iffy at the moment -- the reason is speed of progress. In our times (technological) progress is very very fast by historical standards. That makes it easy to notice if science dies. But that does not apply to, say, the Middle Ages when the progress was so slow it took many generations to produce an appreciable change. During one lifetime things (technologically) did not change much if at all.