I did, but based on my limited experience he only goes deep into questioning when he’s vetting someone or when he sees or hears something that doesn’t seem right. He’s a stickler for details. With an engineers mind for logic and reasoning. You can’t bs him because he is investing in things he is actively studying from multiple sources. You need to know the details and logic behind your approach. The people I saw stumble on the subjects I knew about tended to get flustered when put on the spot and couldn’t provide a logical explanation that made sense or showed attention to detail.
Example, I’m making this up, but it’s a similar type of question I saw, someone is explaining how their application stores data, he will ask, “are you encrypting it?” Response: yes “how?” Response: using XYZ “why not ZYX?” Response: well, we haven’t thought a lot about that yet Response: “well what’s the impact on the processor when encrypting?” Response: not sure...
The engineer thought he was building a app to do X but Bill Gates is operating at a different level, perhaps he has a theory on the future of hardware, or how he wants to deploy this in developing countries. Or he read a recent paper where researchers highlighted the impact of encryption for this specific type of application that he thinks you missed. If he respects you, he will point you into a certain direction and it’s a peer to peer discussion and sharing of ideas, if he doesn’t...it’s painful to watch.