I've seen a handful of people mentioning the possibility of XMR overtaking BTC. Is this just XMR fever talking, or is there some rational basis for this argument?
I see the odds of XMR overtaking BTC being close to nil. That said, I believe there's a high probability it could be a strong 2nd, overtaking LTC as BTC's "silver".
Either XMR fails catastrophically, or it surpasses BTC by a large margin: The use-cases and scalability of XMR cover a much wider range than BTC; most actors suffer for having their private financial details published indiscriminately.
It is only the limitations of bounded rationality and human linear thinking which assign intermediate outcomes the bulk of the probability mass. The underlying fundamentals push the actual mass out to the tails.