QUOTE: “The quality of the MC is an important consideration for PQ rating. We will consider content to be Low quality if it is created without adequate time, effort, expertise, or talent/skill. Pages with low quality MC do not achieve their purpose well…. Important: The Low rating should be used if the page has Low quality MC. ” Google Search Quality Evaluator Guidelines, 2019

Google has a LONG list of technical requirements it advises you meet, on top of all the things it tells you NOT to do to optimise your website. Meeting Google’s technical guidelines is no magic bullet to success – but failing to meet them can impact your rankings in the long run – and the odd technical issue can actually severely impact your entire site if rolled out across multiple pages.
I used to think it could take more to get a subfolder trusted than say an individual file and I guess this sways me to use files on most websites I created (back in the day). Once subfolders are trusted, it’s 6 or half a dozen, what the actual difference is in terms of ranking in Google – usually, rankings in Google are more determined by how RELEVANT or REPUTABLE a page is to a query.

This is why developing a list of keywords is one of the first and most important steps in any search engine optimization initiative. Keywords and SEO are directly connected when it comes to running a winning search marketing campaign. Because keywords are foundational for all your other SEO efforts, it's well worth the time and investment to ensure your SEO keywords are highly relevant to your audience and effectively organized for action.

It makes sense, even in 2020 that this process of labeling is how you create a Search Engine Results Page out of pages Pagerank 2020 identifies, identify spam, identify monetisation trends and promote content first pages and user friendly content above others. You can also imagine that over time, Google should get a lot better at working out quality SERPs for its users, as it identifies more and more NEGATIVE ranking signals, thereby floating higher quality pages to the top as a second order effect. A end-result of this could be that Google gets an amazing SERP for its users.
The SEO starter guide describes much of what your SEO will do for you. Although you don't need to know this guide well yourself if you're hiring a professional to do the work for you, it is useful to be familiar with these techniques, so that you can be aware if an SEO wants to use a technique that is not recommended or, worse, strongly discouraged.