All the patents from 30+ years ago have surely expired. What's to stop someone from creating a kickstarter to recreate all the CAD files/designs for these older

All the patents from 30+ years ago have surely expired. What's to stop someone from creating a kickstarter to recreate all the CAD files/designs for these older machines and open source them. The control system could even be modular so that you could go with an analog system, or swap it out with a raspberry PI controlled system. With those designs out there, surely someone could manufacture and sell these parts and make a good chunk of money.