From an outsider's perspective, it seems like an obvious hypothesis that increased happiness is negatively correlated with depression.

My question is, is this work assessing whether an existing, confirmed hypothesis (e.g. happiness counters depression) holds true for a different population, or is it assessing whether this hypothesis holds true at all [0]?

The paper appears to focus entirely on ASD subjects, so this delineation was not clear to me, at least on an initial skim of the paper.

Also, I feel like a more detailed treatment of hedonic and eudaimonic happiness from the perspective of ASD would have been beneficial in providing a better context to the reader. Maybe this is well-known in the domain?

[0] and happens to focus on this population for access, funding, or other ancillary reasons