Bitcoin functions as both a means of exchange and a store of value. What I think many people fail to realize is that these are two seperate things: bitcoin as the network of nodes, miners and associated source code is the "means of exchange," whereas bitcoin as the entries in the unforgeable global ledger known as the blockchain is the "store of value."
The free market will naturally choose the best payment network (means of exchange) run from the most legitimate ledger (store of value)
1. I expect that for the forseeable future, the market will decide:
best payment network = bitcoin's network
most legitimate ledger = bitcoin's blockchain
But now let's perform a thought experiment by considering a future where the community no longer perceives that the bitcoin network is the best payment network. My intent here is to show that it does not logically follow that the community will abandon the most legitimate ledger at the same time--in fact, the economic majority will strongly favour retaining the same ledger as it is already perceived as legitimate and that is where their wealth and records are stored.
For our thought experiment, consider a Turing-complete system like NXT or Ethereum. Image somehow that one of these systems demonstrates to the cryptocurrency community that Turing completeness is both highly robust and useful
2. So how would this play out?
The community will be overflowing with clones and
spin-offs, several of them trying to redistribute value from the blockchain ledger in a way that they perceive to be "more fair." There will be a great deal of confusion and the market cap of NXT, Ethereum and the clones will be small.
Let's assume that Satoshi is (a) alive, (b) has all his keys, (c) is a rational individual that works for his enlightened self-interest. What could he do?
And herein lies the other thing I think many people fail to realize: Satoshi has more economic power than any of us.
It is in Satoshi's best interest to get behind one of the spin-offs that uses the bitcoin ledger, because he will retain the same % of wealth and the ledger is already perceived as legitimate by the economic majority. If a certain spin-off looks like it already has a head start, he can get behind that, or he could simply launch his own. But at some point, there will be discussion in the community that Spin-off Y based on Block XXXXX is preferable.
Satoshi puts up a bid-wall at say, 1 : 10,000 and a few people dump to him (perhaps those in favour of deleting Satoshi's coins). He then moves the bid-wall up to 1 : 1,000 and a few more people dump to him (those who favour deleting Satoshi's coins go "all in.") The rest of us start to realize the dynamics at play. Spin-off Y is about to become legitimate.
Now every one who didn't dump has a risk-free way to try an increase their percentage of the pie. Speculators scramble to purchase coins of Spin-off Y and very quickly Spin-off Y becomes legitimized.
The only re-distribution of wealth was as follows: those who tried to redistribute wealth from "bitcoin whales" by dumping the spin-off the economic majority supported would lose. Those that realized what was happening and purchased spin-offs from those in favor of re-distribution would gain. And very importantly, the vast majority of the community who remained impartial and did nothing retain the exact same % of wealth.
Remember, Satoshi has a lot of coins. If the "stampede" into Spin-off Y doesn't occur at 1 : 1,000, Satoshi can keep moving up the "peg" until it does. The longer this process takes, the richer Satoshi becomes and the poorer become those who fought the process in favour of re-distribution.
Also note that just the fact that Satoshi
could do this means that he may not even have to. We will all do it for him.
TL/DR: The blockchain will be preserved.1My definition of the terms "best payment network" and "most legitimate ledger" are not subjective or ambiguous. I am defining the term "best payment network" to mean the one most adopted by the community, and the term "most legitimate ledger" to be the ledger that actually gets used by the economic majority. 2Something I personally doubt will ever happen.