Would it cost more than a billion dollars to assemble an elite team of a few hundred people to build a new OS? Would Apple, Microsoft, or Google notice the bill

Would it cost more than a billion dollars to assemble an elite team of a few hundred people to build a new OS? Would Apple, Microsoft, or Google notice the billion dollar cost? Or even two billion? This gives some idea of what is required to keep Linux moving forward. It would be nice if we could see similar stats for MS and Apple. https://lwn.net/Articles/767635/ https://lwn.net/Articles/767635/