It's possible that they tanked because of this news: https://www.aroged.com/2021/12/13/sites-with-pirated-content-will-be-removed-from-yandex-and-other-domestic

It's possible that they tanked because of this news: https://www.aroged.com/2021/12/13/sites-with-pirated-content-will-be-removed-from-yandex-and-other-domestic-search-engines/ https://www.aroged.com/2021/12/13/sites-with-pirated-content... thus removing one of the major reasons to use Yandex.