It's relative to what the female participants self reported as being important.
"My point in the GP post is that they may not actually be overestimating them relative to their personal experience."
Agreed.
"The article isn’t saying that attractiveness and financials aren’t important, but that incels are overestimating them,"
The actual study shows both incel and non-incel groups had similar estimation "errors" but with incels being slightly to somewhat farther from the baseline.
I think it is hard to overestimate the importance of looks if they're the barrier to you simply getting started. But this is the realm of social sciences, so I guess none of this research is concrete anyway.
I would argue that the majority of people underestimate or even lie about the importance of looks.