Of note BI is assumed to replace social security so someone making 50-80k may effectively pay significantly less in taxes prior to retirement but receive far fewer benefits in retirement.
This is why I think BI doesn't have a very good chance in the US. The AARP is a very powerful lobby and their members wouldn't go for a reduction in benefits after retirement.
Do you have voluntary contribution schemes for retirement in the US? e.g., That $80k retiree could've been pumping money into investments designed to top up their BI once they retire?
PS: Of note BI is assumed to replace social security so someone making 50-80k may effectively pay significantly less in taxes prior to retirement but receive far fewer benefits in retirement.