That is probably exactly why they got funding. You can sell it as focus on adding new features and leveraging the best available tools before reinventing the wheel.
They do train their own models now, but for about a year they just forwarded calls to models like gpt3.5T. You still have the option to use models not trained by perplexity.
Wait, are you directly comparing Perplexity and C.ai or Pi? Perplexity is a search engine, Pi is a chatbot, and C.ai is roleplay? Their value propositions are very different