I'd caution against saying one study was "debunked" because another one disagrees with it. Later does not necessarily mean better.
However, in this particular case, the author of the $75k study (Daniel Kahneman, one of the founders of the field of behavioral economics) did an "adversarial collaboration" with the author of the later paper, and found that emotional well-being did continue to rise with income - except for the least happy 20% of people. https://www.pnas.org/doi/10.1073/pnas.2208661120
That sort of makes intuitive sense. Some percentage of people have relationship problems that more money doesn't necessarily help past some point--or even worsens--personal and family health issues that money can only do so much to solve, etc. But especially in HCOL areas, it seems logical that something over $75K inflation-adjusted makes various life decisions and other things easier which would reasonably correlate to happiness at some level. But which is presumably a decreasing utility function at some point for most people.
However, in this particular case, the author of the $75k study (Daniel Kahneman, one of the founders of the field of behavioral economics) did an "adversarial collaboration" with the author of the later paper, and found that emotional well-being did continue to rise with income - except for the least happy 20% of people. https://www.pnas.org/doi/10.1073/pnas.2208661120