Google Search Liaison officially rolled out the latest 3rd June 2020. This latest Google update, regarded as a broad core algorithm is similar to the core algorithm update in the year 2020. Every time when Google makes some update in its algorithm, it put ahead a broad search experience making it more flexible, refined, and relevant for the end-users. At the same time, SEO professionals find themselves struggling as these updates cause unexpected down in rankings of their websites. Also, it takes significant research, and much more effort than previous works, to sustain again in the search engine results.
To give an answer to your question What is the Best SEO Update, I will just convey that every latest update is Best SEO Update than all previous ones. At present the latest core update rolled out on 3rd June, is the best update. Hope you understood.