it's definitionally a payment to all individuals
I don’t see it that way at all. It’s a guarantee of a universal basic income, not a free for all giveaway. Or is there another name for what I’m calling UBI?
It can be either.
Economically, there's no difference between giving $X to everyone, and then taking an extra $X in tax from 90% of them; And giving $X to just the 10% of people who you weren't going to tax.
The details of the implementation are about efficiency.
If you already have a huge bureaucracy devoted to calculating each person's tax bill, then it's cheaper, easier, and more efficient to pay the UBI to everyone, and then have it clawed back by the existing taxation system, than it is to set up a second huge bureaucracy devoted to calculating who is entitled to the (no longer U)BI, and to ensuring that nobody who isn't entitled to it claims it, and/or that everybody who gets it declares it on their taxes.
"Pay it to everyone" is a cheap policy to enact; The only bureaucratic requirement is to make sure everyone gets it once, and only once; That is, that each claimant is a single unique individual.
Whether "everyone" means 'all citizens' or 'all adult citizens' is a detail that needs to be resolved in any specific policy, of course. But there are lots of details, and the assumptions being made here abkut those details are a large part of the reason why there's so little agreement on whether or not UBI is affordable - the actual answer is "it depends".
As I envisage it, a UBI looks like this:
Every citizen over the age of 18 gets paid a weekly sum of $X
All other government payments directly to citizens are scrapped.
The personal income tax system is made more progressive, and simplified by the removal of deductions of
all kinds.
Ideally, the tax rate would be calculated using a smooth formulaic approach, rather than a bracketed, system (see
here for examples of how this could work).
The tax formula would be set such that total tax revenue after the change would be equal to total tax revenue before the change, plus the total amount disbursed as UBI payments.
Tax would be paid on all income above the UBI (or simply on all income; In a smooth tax regime, these are functionally equivalent).
All minimum wage laws are scrapped. Employers can pay as little as their employees will take, or can employ people for nothing as volunteer workers, if anyone wants to work for nothing (eg "tips only" jobs).
In the implementation phase, employers are required to cut wages by $X per week across all employment sectors; Employee total income on week one of UBI should be equal to their total income the previous week, the difference being that now the employer only pays the amount above $X.
For employees whose incomes are below $X, the employer and employee would negotiate a new pay structure (which might be "tips only", or a small wage, or the elimination of the job altogether; or any other mutually acceptable arrangement).
Future wage and salary levels are purely a matter between employers and employees; Raises and/or pay cuts by mutual agreement. If employees are unhappy, they can quit; If employers are unhappy, they can fire.