Oh, they will give even dumber answers than that.
Add a space after the #s. Not sure why it works that way now.
There are cases of monopolies that are the result of a single competitor being so efficient, cost attractive and capable of serving its market that it becomes a "natural monopoly" for whatever period it can sustain that. It's the one type of monopoly that isn't viewed dourly because it tends to represent the best possible result for both sides of the equation.
Standard Oil's monopoly, and its inability to maintain it (and why), is described by David Friedman in the Machinery of Freedom. While I can't really do the response real credit here, the simple answer is that it works quite the opposite to what you imply -- without government intervention, Standard Oil couldn't keep competition from breaking their hold. But with intervention, monopolies are more easily captured and maintained.
You can find some of Freidman's answer here (PDF, see the end of page 21 and a few beyond as well as other parts that speak to Standard Oil and more specifically to Rockefeller's unsuccessful strategies.) In all, it's an EXCELLENT read if you're really interested in how free markets topple rather than uphold monopolies and oligopolies.
It's definitely an example of market preference, but Bitcoin doesn't have a monopoly even if it has market dominance. The two are not synonymous. And even then, its dominance is a feature of its appreciative value the way gold might be preferential asset over other metals, not because of the market's preference for Bitcoin's utility (or lack thereof) which is outmatched by other cryptocurrencies. That lapse in utility is also becoming magnified in the current day. Bitcoin's reign is unlikely to be everlasting as a result, nevermind the one-true-coin believers.
The Bitcoin example is arguably a poor one. Its market dominance exists because it's the most appreciative asset as cryptocurrency's first mover. That is to say, it's naturally the favored coin for speculation and hodlers because it's the best performing asset in human history. This is akin to saying that gold has market dominance in the metals markets. In that sense, neither Bitcoin nor gold really relates to the type of monopoly/oligopoly market supremacy you're discussing wherein an active market competitor controls the heights.
It stands for Decentralized Finance.
Definitionally terrorism. Therefore, if Biden/US sends more money and arms to Ukraine, they are de facto sponsoring state terrorism. I know, everyone here is surprised.