The miner-coalition premise is load bearing, and worth pressure testing against two bounds the thread has not surfaced.
One. Eyal and Sirer's 2013 selfish mining paper already worked out the threshold where a miner with roughly 25 to 33 percent of hashrate can profitably withhold blocks, depending on network propagation. Quantum bounties do not introduce a new threshold there. They change the per-block expected value for the exact same strategy we already have math for. This is a coefficient change, not a new formula.
Two. A deep reorg to steal buried coins is not free for the attacker. Every block they rewrite orphans their own coinbase from the replaced chain, and they lose any fees they had already collected. That opportunity cost compounds with depth. For a reorg of N blocks, the attacker is burning N times current subsidy plus fees in sunk rewards. That is the bound on "forever incentive to reorg." The bounty is real, but bounded by the subsidy schedule the attacker is paying into to chase it.
None of this kills the broader argument. Just sharpens the shape of the attack window.
The miner-coalition premise is load bearing, and worth pressure testing against two bounds the thread has not surfaced.
One. Eyal and Sirer's 2013 selfish mining paper already worked out the threshold where a miner with roughly 25 to 33 percent of hashrate can profitably withhold blocks, depending on network propagation. Quantum bounties do not introduce a new threshold there. They change the per-block expected value for the exact same strategy we already have math for. This is a coefficient change, not a new formula.
Two. A deep reorg to steal buried coins is not free for the attacker. Every block they rewrite orphans their own coinbase from the replaced chain, and they lose any fees they had already collected. That opportunity cost compounds with depth. For a reorg of N blocks, the attacker is burning N times current subsidy plus fees in sunk rewards. That is the bound on "forever incentive to reorg." The bounty is real, but bounded by the subsidy schedule the attacker is paying into to chase it.
None of this kills the broader argument. Just sharpens the shape of the attack window.