There is no decentralized solution to the BGP problem. Period.
For a moment, just consider this; you are saying that there is no solution to BGP in trustless anonymous systems, but: If you take a snapshot of the current bitcoin hash rate and equally divide it out between N generals of fixed and equal hash rate, this is now classical BGP. You must be forced to concede that you are in fact saying that there is
no solution to BGP at all, which is clearly false.
Look he is saying there is no "unconditional" solution, which is absolutely correct. There is a solution, which may work, or may not work, depending on the state of the world when it is applied.
That is very much the same as Bitcoin, and stated as such by Satoshi in the white paper. Bitcoin is not unconditionally anything. If a majority of CPU power is conspiring to attack it, then it is failing.
Agreed, but please note my point is deeper than that.
I am saying that in a decentralized, trustless, Sybil-attackable scenario, there is also no
conditional solution to BGP, because the participants have no way to conjecture the probabilities of 51% attack (nor does any solution to BGP provide all participants a consistent, provable observation when the system state is attacked).
The condition of count of traitors has only utility in applications where the probabilistic rate of traitors can be conjectured.
I have also I think argued convincingly that Satoshi's PoW design (and every decentralized consensus design) must trend towards and rely on centralization. Thus the asymptotic probability of 51% attack is ~1.
Though Bitcoin does have a somewhat nice recovery property in that the failure only persists as long as 50% of the CPU power is conspiring to attack it. Unlike, an airplane for example. If too many components "temporarily" fail, then it may be catastrophically disassembled before they recover.
I can think of scenarios where that isn't necessarily true. For example, such an attack convinces speculators that the attack can be repeated at-will and so they flee the coin. Crash and burn.