> Whereas NIT likely requires people to continually submit tax returns stating their lack of income (which is potentially more stigmatising).
It also means a lot of people simply won't get the benefits. In the U.S., a lot of people who are eligible for welfare programs never take advantage of them because of the administrative hurtles (to take one example, "Only about 1 in 6 people who are eligible for child care subsidies actually get it"[1]). I'm starting to think more and more that this is by design.
Even if you're one of the people that gets the benefits you're eligible for, it's still a burden (imagine having to do your taxes several times a year), and you are subject to the whims of policy makers that want to beat up on you for political credits. So you had some states requiring that welfare recipients get drug testing. If you had a similar requirement for Social Security, people would be livid and through the politicians out on the street. But when this kind of stuff is done to the poor, a lot of people have the attitude that the impoverished deserve to be treated badly.
[1] www.npr.org/2016/08/21/490822086/the-financial-trials-of-child-care-for-working-families