Because a big part of that value comes only after - and only because - whoever registered the name invested into that brand, sometimes by continued business and

Because a big part of that value comes only after - and only because - whoever registered the name invested into that brand, sometimes by continued business and reputation, sometimes by marketing. For example, the name ycombinator.com has some value on its own, but I think you won't contest that the vast majority of the current value of that name arose only because a popular community was ran on this domain name for decades, and if hackernews was instead run on scombinator.com or whatever, then the value of ycombinator.com would be just a fraction of what it currently is.