I believe they are on to something, but wouldn't it be much better if the sample size was larger than just 57 people?

This is a good question but not an invalidation of the study. People underestimate the cost of doing large scale surveys, first year researchers become painfully aware of it. There are lots of research were you try to get a quantitative result cheap. But most costs a lot of money (the big studies are usually very well spent money imho)

Example: five years, 10000 participants, $170 million https://www.nih.gov/news-events/news-releases/nih-awards-170...

Of course but I'm sure they made the sample size as large as their funding permitted and it's better than nothing.

Larger sample sizes allow you to detect smaller effects. Since a signal was seen here effect size doesn’t seem to be the problem.