Isn't it ironic that the libertarian bitcoiners, champions of laissez-faire capitalism, are betting all their life savings on the hope that the Satoshi Bitcoin will be one day the only cryptocurrency in the market, so that they can charge monopoly prices for it?

I see no irony there. I am not sure you understand the core values of libertairianism in light of this comment. Libertarians tend to defend what others call monopolies.
Perhaps I don't.
A monopoly is the opposite of free market by definition, so how can one be in favor of the latter without being against the former?
If libertarians do not object to monopolies, why do they object to government, which has by defintion the monopoly in many fields (army, criminal punishment, money issuance, etc.)?
Now you're getting warmer. Libertarians tend to oppose coercive monopolies. From the party platform:
2.6 Monopolies and Corporations
We defend the right of individuals to form corporations, cooperatives and other types of companies based on voluntary association. We seek to divest government of all functions that can be provided by non-governmental organizations or private individuals. We oppose government subsidies to business, labor, or any other special interest. Industries should be governed by free markets.
Now. Your comparison of bitcoin holders (even hoarders) to monopolies is another issue. How can you make this comparison? There is no monopoly there yet. In fact, the US Government's holdings will eliminate the possibility of any non government monopolistic BTC group even forming. There is no monopoly now, and it will be hard for there to be in the future.
I think your political bias might be showing a tad.
