I don't think they're claiming to actually anonymize them. Seems like it's just a stylistic choice to not affirmatively identify them.

And avoiding a potential libel suit.

It's only libel if it isn't true.

To save the rest of you some trouble, the startups are Oyster ("e-books"), Mixpanel ("big data"), and Github ("open source").

While it was probably a legal decision, I actually liked how it worked on an artistic level. As a reader I was trying to piece it together myself. And it also left a feeling of, 'well, this is a specific company she is talking about, but at the same time could easily apply to dozens of others in the industry.'

So they can't sue back.

Ah yes, the technicalities of our wonderful justice system.