Epic used the term but did not introduce it though, the term was already being used much earlier than their FAQ. You can google the term and find hits dating years back from sources which have nothing to do with Epic. One example,
this question from 3 years ago.
Did you read the motion? Nothing in there pertains the "general computing" argument. The whole issue is about financial statements: the deposition states that the Xbox is sold as loss-leader, Apple wants the figures supporting that claim, Microsoft doesn't want to expose their internal financial figures to competitors.
But again, you don't need to trust me nor Epic nor the deposition: open a search engine, look for the term yourself and you'll quickly find hits dating years back like the example I posted above.