Monero is and will be a niche coin.
Until it isn't. That particular niche is a peculiarly viral one, under the right conditions - conditions such as financial repression, bail-ins, quantitative easing, negative interest rates, confiscatory taxation, capital controls, counterparty chain failures, trade globalization, commodity deflation, sovereign instability, overregulation of trade, graft and extortion, kidnappings, class war, Owellian surveillance, corporate secrecy. Oh, and then there is scalability...
If the world were becoming a safer, more congenial place, in which human dignity and self-determination was in the ascendance, the importance of privacy might erode over time. If instead it becomes more dangerous, less stable, if the power of the rapacious rises, and confidence in the social, political, legal and economic paradigm declines, then the appeal of privacy, and it's market value, will rise, or even explode.
My view is that the probability mass is firmly on the latter side, culminating in a failure of old paradigms, and their replacement with new ones which are more robust to the causes of recent instability, and better adapted to the new opportunities which arise in the meantime.
We can calibrate from the mid-2013 precedent what marketcap is suppored by DNMs alone (accounting for their growth, and scaling by present market share). It is enough to make it feasible to transact in a freely floating crypto at most practical sizes. Securing wealth will drive the big gains after some such threshold is passed. Confidential corporate transactions would suffice to take it "mainstream" soon thereafter.
