Bitcoin has no value. It has a price, but not a value. Dutch tulip bulbs, 2008 Sacramento real estate devlopments, Pets.com stock all had prices at some point, but their value was always less than its price.
Your examples contradict your first point.
Tulips have value today, a lot less than the bubble. Sacramento real estate has lots of value today. Pets.com was worth something even when it went bankrupt, even as little as it might have been.
$4.3 billion isn't a very big bubble besides. Not even a drop in the ocean of global currencies.