I think it has a value because people understand it, we can see how the engine was made and since it is a fair deal for all then people decide it has a value. The value is variable because is based on a market, but what we know is the value will never be zero.
I don't think so.
I'm pretty sure that people who actually understand Bitcoin is only a small minority. All they need to know is that Bitcoin is decentralized, trust-less, unconfiscatable, and has a hard limit. I think knowing those characteristics alone will be enough for the typical non tech-savvy person to know that it's worth something.
I believe the people who truly/deeply understands Bitcoin is closer to zero, than the "small minority". The clueless includes me. Haha.
Ask what Bitcoin is to different people, and they will give you multiple different answers.