The problem, of course, when all contributions are "limited" to those within the company, that the talent and expertise required to keep things going exist just in the company itself, and not in the overall open source community. So when the company behind the tech "goes away", all the knowledge does too. It's for that reason that open source that is totally under the control of one company is so dangerous. Sure, you have the ability to fork, but the reality is that such a fork is almost assuredly doomed to fail. You really are beholden to that company.