I don't think scarcity creates value by itself. Sure, if there were a trillion bitcoin and everyone had 20 million it wouldn't be worth 40k per bitcoin. So in that sense price*supply had to be a low enough value. But scarcity itself is not what makes bitcoin valuable. Fixed scarcity maintains value. I'd say what "gives" value is not what "maintains" value, but what people do that make value increase. Market adoption, promotion, value "creation" in terms of improving the software and the environment in which it moves. Ecosystemic maintenance and improvement gives value. Value is also perceived, not objective, so marketing gives value.