Not only that, it's much more legal to be racially biased in who you choose as your customers. The laws in the US that require nondiscrimination in hiring, regardless of how effective they may or may not be, don't apply at all to choosing a NoSQL vendor or whatever.
Which part isn't plausible? There's plenty of evidence that competitors are biased in various ways. For tech startups, customers and investors are rarely aware of the racial mix of employees, unless maybe they're in the news for not being diverse enough.