She was testifying on behalf of epic. She was undoubtedly in contact with epics lawyers ahead of her testimony. She claims to have documents that back up her story but she never gave them to Apple or the court. There is a motion pending to have her testimony considered not credible. I wouldn’t say her testimony “definitely” shows anything under the circumstances.
Apple's motion to dismiss her testimony is centered about the claim that the Xbox console is sold as loss-leader and lack of documentation provided by Microsoft supporting said claim, not about the "general purpose" distinction.
In general, the term is in widespread use since long before the Epic case was even a thing: the question is more what the legal interpretation and relevance will be in this specific case.