In the linked presentation Bitcoin is exposed Bitcoin as a fake investment product, which as such, is a total waste of energy. This also applies to all cryptocurrencies.
Why is bitcoin a fake investment product? Or, to put it another way, how do we even differentiate between real and fake ones. Well, it's easy. In a real investment product, your investment of property or work is invested into something actual, which in the future, can provide you similar benefit. In a fake investment product, your investment is not actually invested into something, but is rather, just transferred from you as a new investor to old investor. Historically, there is no exception to the rule that all such products end up collapsing.
The rest here:
https://youtu.be/N5RKm7_scL4