This is commonly misreported. A 2010 study found that answers to questions like "Did you experience a lot of stress yesterday?" leveled out between $60,000 and $90,000. How satisfied people said they were with their lives continued to increase.[1]
Kahneman actually speaks to this pretty well in his TED talk about the two types of happiness, but the parent comment seemed to be speaking to the first type (the 'reducing stress' happiness, not the 'reflecting' happiness). You're right; I was trying deliberately not to get lost in the weeds on the details but it probably just looks lazy instead.
[1] https://www.pnas.org/content/107/38/16489