I do admit that the security of a sybil-resilience foundation for QV may be affected by the overall set of benefits which owning a proof-of-personhood brings. This is especially complex because we can’t prevent undesired use cases from overloading a provable personhood system in an transparent and unpermissioned network.
If you say “it’s too easy to pay people”, you’re certainly not wrong, but that is mostly independent of QV. The question should rather be how well a vote-buying attack would scale in any of the voting systems.
In today’s OpenGov, a single whale can change the outcome of referenda. Buying votes may even be more of a concern, because it takes just one corrupt whale to accept a “dividend” on a treasury proposal they approve.
The question is, therefore, if we can add enough friction to scaling a vote-buying attack in QV. I believe we should seriously look into vote privacy and receipt-freeness. What’s the point in paying someone for their vote if they can only prove that they voted, but can’t prove to you how they voted? That would certainly make vote-buying much harder to scale. There is plenty of research on this topic in eVoting in general and the topic would better be discussed separately IMO:
I think we should distinguish the problem of sybil-resilience (making sure every human can vote once) from vote-buying (making sure every voter votes according to their honest opinion). The latter is very blurry anyway, because “free will” isn’t “free from manipulation or external influence”. Even perfect universal suffering is affected by money: The party with more money to spend on their campaign does have an advantage over the less funded party. While that certainly isn’t “corruption”, it still is a plutocratic force but has nothing to do with sybil-resilience AFAIU.
I agree that we should not promote a “UBI for the criminally minded”. Still, I can’t overlook the balancing effect it would have globally. It would diffuse capital into underdeveloped regions where many votes could be bought for relatively little money. This is certainly not the vision I’m advocating, but at least there’s a small upside - in contrast to OpenGov of today where potential corruption of whales would enrich them even more without any redistribution effect.