If you're going to count stuff invented before 1970 that didn't make it to market for 20+ years, then you also have to count all the technology that is being developed today but won't be market ready for 20 years. Carbon nanotubes, nanomachines, genetically customized medicine, Turing capable AI, etc.

Of course, since we don't know which of those technologies will be viable, we mentally don't count them.