How does Worldcoin plan to solve for people in wealthier countries not wanting to scan their eyeballs (because the UBI isn't meaningful enough)?

By getting governments to do it for them with KYC regulations

Or a more dystopian answer may be they will buy them on the black market.

The government doesn't care who does the proofing so long as it results in their ability to ensure taxes are collected. BTW, the US government already outsourced ID verification to ID.me

Why would government want to give up control of the proof of personhood identity monopoly?