Answering the question "why does Y have value X" with "because people/someone are/is willing to buy Y at price X" is technically correct but a cop-out. When people ask why something has value, they are typically asking
why someone is willing to give money for it, what's the motivation. And the reason why people are willing to pay for something can be very relevant, especially if you want to figure out whether something will rise in value or collapse.
There are many reasons to want something, but broadly you can argue that you either want something because you believe owning the thing will make your life better in some way (food, housing, transportation, ...); or you can want something because you think someone else will pay more for it later down the line, in which case the value of the thing is entirely speculative to you.
Some things are not entirely one or the other. People wanted tulips because they are pretty. Eventually they became a status symbol, demand grew faster than supply, and quickly people started buying tulips not because they wanted them, but because someone else might pay more later. So tulips became a speculative bubble, which eventually collapsed.