Although that's technically true some historians differentiate between the Kievan Rus and the Russia Tsardom as the Rurik dynasty mostly ruled over the Kievan Run during their reign of the east (of course except for the years preceding the times of trouble up to Tsar when Tsar Michael took over as you mentioned)
You have reminded me about earlier Russian history through this article. I hope to explore a bit of the history of the Rurik dynasty soon as I have done in a previous article about Ivan Grozny a.k.a. Ivan the Terrible. Thank you for the feedback!