Technically, LLVM started as a research project at UIUC, and then Apple hired the principals and adopted the project in 2005. The LLVM website is still hosted by UIUC, and Google and other companies are also significant contributors.
Maintaining and growing an existing tool with its existing developers who you bought in is a good thing and to be applauded, but doesn't necessarily mean the company is good at tooling in general. The cultural requirements are very different.