Some of the statements are a little questionable. The Caucasus was also important to Russian romanticism (Lermontov, etc.). Voluntarily or otherwise, Russians did go to Kazakhstan: they were the largest ethnic group there in the 1960s and 1970s.
Crimea is no South Ossetia. This is not some remote, mountainous Georgian village inhabited by some dubious ethnicity that Russians have never heard of. Crimea is the heart of Russian romanticism. The peninsula is the only part of the classical world that Russia ever conquered. And this is why the Tsarist aristocracy fell in love with it. Crimea symbolized Russias 18th and 19th-century fantasy to conquer Constantinople and liberate Greek Orthodox Christians from Muslim rule. Crimea became the imperial playground: In poetry and palaces, it was extolled as the jewel in the Russian crown.
He detected one aspect: the Byzantine vector present in Crimea and absent in the Caucasus or in Asian colonies. Remember that the Russian idea, when there still was a Russia, was to connect to Constantinople, the Second Rome.