I have some experience in the Russian-speaking segment of the Internet. To all of the above I can add the following:
1. In Yandex, the main role is played by behavioral factors and not by links.
2. In highly competitive topics, in order to advance in Yandex organic search results, you need to have good behavioral factors, and since the site is new, there is no traffic, so many webmasters buy traffic to their site in the same Yandex direct (analogue of Google ads)
3. In Yandex, code validation has a great influence on ranking (in Google it is not so important)
4. It is also good practice to create so-called turbo pages (light pages). Sites with turbo pages have an advantage in ranking.