As far as I am concerned the jury is still out on whether that will be the case, and if it does turn out to be, whether the system will have bloated beyond the capacity where it could realistically be operated by a large pool of individuals. The ability for the operational infrastructure to be cheap and widely dispersed is THE thing which gives Bitcoin it's backing and strength in my opinion. As that erodes so does my confidence in the solution.
Most of the bitcoin network is not the technical network of computers running Bitcoin protocol. Bitcoin is in actuality
a socio-economic power network of hundreds of supernodes and 100,000s of active nodes. That the majority of them don't have the Bitcoin client, is only economical, division of labor. The important thing is, Bitcoin is open source, so that the economic majority gets to choose the rules, not the coercive minority, and this will forever remain so, because of the design.
I disagree with this rosy analysis. I put more emphasis on the actual hardware and network topology needed to allow the system to perform anywhere near it's potential.
But you bring up another entirely different potential failure mode which I consider as possibly coming into play. That is, if the system is not working reasonably well for a wide range of participants, the participants could very well be drawn to something else. Unlike with gold, it would be very low effort to actually develop a crypto-currency system upon which the masses could coalesce. The bothersome part is that there are limited means to make the system work truly well for all but the early adopters (like most of us reading this probably are.) Ultimately Bitcoin rests on the same 'historical record' as gold, but where gold's history goes back thousands of years, Bitcoin's goes back to 2009.
There is actually a link between my two concerns. That is, if the Bitcoin network becomes sufficiently centralized and riding entirely on a backbone consisting of 'supernodes', it will be that much easier to attack the system and degrade it enough to make it even less appealing to the newcomers than it is simply due to the expensive proposition of 'buying in' at what will likely always appear to be the top.