This is where there is an advantage in targetting a sub-niche that is much narrower than a topical niche/category. Whilst a larger authority site may get the boost just because it has authority for the more general search terms within that category, they can often be outranked by a smaller niche site targetting a specific sub-category within the larger category.
This is where good page titles and meta descriptions inviting click through are just as important as the landing page/site quality of the smaller niche site. I have observed in a number of cases a new page on the niche subject entering SERPs at the bottom of the page 1 and then over the time creeping up eventually outranking large authority sites that held top positions.
In my observations I think this was not because of backlinks (gained neglible amount), I would rather speculate it was because of user metrics the new entry showed over the time. From my observations of several sites, it took 3-6 months for the new niche entry to outrank a larger authority site.