There's no general agreement among libertarians on what's the best money.

I'm against a gold standard because it's dumb. Gold standard worked in a time of industrial revolution, which cancels out the negative side of gold standard. Costs and prices went order of magnitude down and then there was more gold for everyone.

Literally the steam engine and electricity and light bulb and radio were brought at the time of gold standard.

Okay then, how would you build a trustable banking industry without some certain central authority?

We can't do that.

We can't eat, drink or use money as shelter. It's with food, liquids or bricks that we can do that.

There was an argument to be made during the start 1900 about "availability" (liquidity) of money. That's all gone in the past.

Money is just an account system, and it's all just numbers in a computer database.

We can't eat numbers.

Technology made money extremely available. That also made it extremely fragile.

The best system we have so far is to have a "free market" of currencies, banks, and customers. The three of them together via trial and error decide what's best. And during that process, mistakes will be made.