MMmmm, I understand the sentiment. But I think you'll find that's not true. The Oracle database, alone, has a long history of engineering behind it that has not truly been replicated by other products. Of course, this is really only relevant for corner cases, but these exist, and they're usually folks who have big budgets (like governments, or large enterprises). And at that level, what they're paying for is not the technology as-shipped, but the support ... which means you have a "throat to choke" in terms of lawsuits, but could also mean building something that's proprietary for your business.