I find it interesting that you would start a post on Cryptocurrencies and give the merits of "basic natural law and property rights" I say this because I see Cryptocurrencies as a violation of those same natural laws. As a matter of fact I see it as fiat! Please notice I didn't say government fiat. As I'm sure you know, but others may not "fiat" means "So be it" , and once only a king and his ilk could say "so be it" and have what he said come to pass. However now most of the kings have been replaced with governments so people relate So be it (fiat) to what governments might do. Hence fiat (So be it) money! People want to take back their power to say So be it for their own benefit, and that is all well and good as long as there is no negative affect by your right to say those words to others. Cryptocurrencies in their current form violates the basic natural law that you talk about. However before I can talk about how I think they do that, I have to give you my understanding of what currency is, and what is the difference I believe there is between currency and money.

This is a source of money!

This and any of the other commodities

https://modernfarmer.com/2013/12/chop-wood/
And I am not talking about making it into paper and then printing symbols on it.

This is not a source of money

https://www.dreamstime.com/stock-photos-globe-server-image3002843
And it is not (as some say) the new type of money. It is not even currency unless it is somehow connected with human effort. Money comes from a person's effort. I make this statement because some have called Cryptocurrencies money and that is where the evil side comes in.

a blatant, calculated, unapologetic and brutal denial of the immutable biological and metaphysical reality of individual self-ownership.

I believe that "self-owership" referred to is in direct connection with the fruits of ones labor. A very important question, is a computer's labor 100 to 1000 time more acceptable than a man or woman's labor? Right now you might reply to that question with "YES! because it is going up". Let's take a look at the closing numbers right now Bit-coin is currently at the 14,500 level, the 200 day moving average is at 4,700 which is down 68 percent and the 200 week average is at 1,365 down 89 percent. So you can have a 70 to 90 percent retrace and Bit-coin and it would still be in an up trend. However I don't think people who got it some time back should be to happy with those numbers. Because it shows that people are taking profit and to the people that are taking profit that's a good thing, but for the others, not so much.
Those who have not taken profit.

The Island of Dr. Moreau

Are We Not Men ?

So do I think Cyrpto's are a good thing?

“Venezuela will create a cryptocurrency,” backed by oil, gas, gold and diamond reserves, President Maduro said in his regular Sunday televised broadcast! This is my idea of a real cryptocurrency. What is the reason that people dislike the dollar other than taxes ?

which could be remedy by a flat tax as there are in many nations states

It is because the dollar is printed without anything backing it. You might reply "that's not true it's back by oil." Well for one thing it's not backed by our oil, also that is very quickly becoming a thing of the pass. I personally think that steemit could have a good platform for cyrpto, however the inequality are glaring (which is the reason I stop posting and only comment). This could be a post but as a post I would not make one steem from it, but to give an opinion on a very important subject, to me is worth the time. So, I understand that by this time the reply is a bit much! I will only make one more point. Someone once said to me that cyrpto are back by mathematics. I think I'll let a respected intellect reply to that for me.

Of cause this is just one man's opinion!
Oh! as far as cyrpto taxes " I am for a flat tax! So no to taxes on cyrpto's! Just a tax on all sales only!