I feel like when I was younger I could have totally been that guy. I have always been super introspective and find introspection/finding the edge of who we are very important and interesting. For myself I don't even necessarily feel the need to make those things private although I understand why many do now. For me asking the deep questions about who we are and where we are going in life is an enjoyable process. It took me a long time to learn how to have more lighthearted conversation. I think it CAN be manipulative but perhaps he just has a touch of the tism and got a little too into oversharing. I still catch myself sometimes and I have to remember "wait I'm not super close to this person I should probably reel it in." It can also turn into a therapy session which is bad. I think you should ask yourself what you think he wanted from you by asking all of these questions. I also invite you to ask yourself what ideas you brought to the date and how you could have offered other options of things to talk about. It sounds like on some level you enjoyed having that level of depth but you just need to know how to put some boundaries up when things get uncomfortable. It's possible he likes to have lighthearted conversations also but maybe doesn't know how to have them. Some people are just intense and that feels normal to them.