Linux definitely wouldn't be stranded without corporate input. A.) A large portion of Linux has been written by volunteers, not employees of a corporation giving back to the project, and B.) The majority of the time these corporate contributions are things like drivers for their own closed source hardware to work with Linux. I've only ever contributed to open source voluntarily, with the exception of three pull requests that were written so that, surprise surprise, our corporate shit could work with the open source shit. I'm not saying there wouldn't be disruptions if we axed all that code, just that it wouldn't be the project-ending amount you suggested.