The Google white paper specifically mentions that its algorithms can sense when a query is related to YMYL (your money your life) and related content, and then the adjustment of the weight of the ranking algorithm is ensured for those particular queries. The SEO industry was not really sure if Google is actually doing this, so, that debate should be put to rest now.
On page 13 of Google white paper it is mentioned that, when its algorithms detect that a query is related to an YMYL topic, more weightage is given in the ranking system to the factors like Google’s understanding of the dependability, expertise, and reliability of the pages presented in response.
This means that Google values expertise, authoritativeness, or trustworthiness (EAT) in offering the ranks, and when it comes to YMYL queries, the EAT becomes more important. Google has also mentioned that its algorithms recognize signals about the pages that correspond to authoritativeness and trustworthiness. PageRank is the best known signal among these and it utilizes the web links to figure out the authoritativeness. Thus, out of EAT, A, and T are mostly dependent on links and PageRank.
The primary mention of these factors pertains to Search Quality Raters Guidelines but it is also an important part of the algorithm for query analysis (might be related to RankBrain) and for the adjustment of weights in the ranking system.
There is nothing unusual to it because Google does it for multiple sections like finance, pharmaceuticals, adult, health, and so on. Thus, this should not come as a surprise to anyone. However, it is great that Google spelled it out in the YMYL sector and clarified that they utilize the EAT signals, in the Google white paper.
It is also important to mention that Google uses ranking signals for the determination of EAT and EAT is not one of the ranking signals by itself.
Forum discussion at Twitter.