Omnisharp is mainly community members getting together to produce it. The idea was originally devised by Jason Imison. A couple of MS guys wanted to get involve

Omnisharp is mainly community members getting together to produce it. The idea was originally devised by Jason Imison. A couple of MS guys wanted to get involved and now VSCode uses Omnisharp under the hood. So whilst there are a couple of MS guys involved and VSCode uses it, Ominsharp is a community project