In order for technological advance to drag us out of the hole we are in, we need functioning markets with functioning price discovery, and, in my opinion, a UBI. To me the former implies hard, non-inflationary money, with privacy and fungibility baked in, while the latter implies an inflationary fiat or a freigeld which floats against the hard money. I do not believe that a knowledge-based economy can function without both forms of currency, at least not without the adoption of a regime of continuous recurring atrocity (which is the current trend). The former is required for capital formation, required to build enterprise and conduct research involving capital equipment, while the latter is required to support excess consumers.
...how [can] a whole global, or even national society, ... function on a UBI if that society were to use an asset like Monero or even Bitcoin as the new currency. It's not like everyone can afford to put out the same hash rate to mine... or if it should come from somewhere, where should it originally come from?
I tried to describe a dual currency model, in which a fungible hard currency (monero) facilitates the productive functions of capital markets, and an inflationary or freigeld-class of currency floats against the hard money, at some market value. It is the issuance and distribution of the latter which provides UBI. But in order for capitalists to sell their goods, they need to accept and exchange freigeld.
Remember Gresham's law. The currency undergoing inflation or demurrage will see transactional demand, while the hard money will see reserve demand. The clearing exchange price will depend on where the ISLM curves of the two currencies balance.
The other way would be to put a gun to someone's head and make them pay for some unproductive loser's UBI. Which would be (1) immoral, (2) counterproductive, and (3) unsustainable. That is how it works now, except hard money is suppressed by overt threats and covert conspiracies. It won't scale to UBI, in my opinion.