I'm forever blowing bitcoin
They have no intrinsic value
I'd argue that nothing has an intrinsic value. Economists may use that terminology, but even in that restricted technical usage it is gibberish.
Value is subjective, not objective. Some people love Bounty bars; I, whilst liking chocolate and liking coconut, find that particular combination to literally make me gag. Some people think works of art by Picasso are wonderful, I think they're garbage.
When I say all that, economists counter by saying what they mean by "intrinsic value" is the cost of the labour used to produce the item. Which is still bollocks. That's an intrinsic cost which is not necessarily related to a subjective value. For example, take the Vega Spectrum: if they ever manage to produce even a working prototype that will have been at great cost but the item will have little value.
Anyone who thinks that anything has an intrinsic value, whichever way they define it, is severely deluded. So deluded, in fact, they probably think bitcoin is intrinsically worth a lot of money.