Well, the technology for them is far from recent, the process control and chamber geometry design to allow the needed precision and uniform-ness at the throughout needed to not be extremely expensive, however, required cheap microprocessors for a good decade to develop the required skills in control engineers to then actually go and make a machine like this.
And the computers suitable we're still triple-digits in the 80's, so this only really started to deploy to factories ~25 years ago.