BTC will be very hard to replace, but DRK already has the fundamentals that BTC lacks. I'm not saying DRK will be the replacement. I'm just pointing out the inevitability of antiquated technology to be replaced by better stuff. I stopped using my 1core 32bit AMD chip about 6 years ago...
I think you're being highly selective in deciding what you regard as being "fundamentals".
DRK has certainly improved on Bitcoin in several ways - algo efficiency, anonymity etc - but those are technical properties, not necessarily "fundamentals" that impact on it's status as a reserve currency.
Bitcoin has been superseded technically by almost all new altcions, but they have never put a dent in its value - not even litecoin did. So technical superiority isn't "it".
In fact, your computer hardware example actually undermines your own case because if you look back at the evolution of the digital industry, hardware technology hasn't been one of the "fundamentals" while those areas that have been have persistent against a wave of "improvements" on their original design:
- the Unix operating system: 41 years old, now underpins all new Apple desktop hardware, not exactly considered "antiquated"
- The ASCII and Unicode character codings for information interchange, 50 and 27 years old respectively
- SQL, Structured Query Language for database access, 44 years old and only getting more widespread adoption with every year
- TCP/IP that underpins the internet: 40 years old
- all the high level internet protocols and markup languages - http, smtp, html etc 24 years old and getting more widespread adoption with every year
What these show is that the "true" fundamentals do not get superseded. They persist and consolidate with time and adoption.
If Bitcoin is still around in 20 years you can bet your bottom dollar that it's not going to get removed from "reserve currency" status just because its algo is outdated. See the things I mentioned in my last post - those are the real "fundamentals", not technical characteristics.