Likely didn't want the risk of Russians looking too closely at China and triggering too many fond memories. China owes the people in ex-Soviet countries for the leg up. It was never a perfect relationship and things went sour before it could blossom. But the Soviets did help the Chinese and we're far enough in the future that mistakes can be overlooked in favour of focusing on the sentiment.

And now? Russian capitalists will try to avoid it. But one option is a relatively peaceful transition back to socialism for Russia. The longer Russia gets closer to China, the more likely this becomes as Russians see that (a) it's needed for self preservation and (b) the Chinese have resolved many of the problems that weakened the USSR. Meaning it's both necessary and viable. Due to the CPC's historic debt and the general internationalism of socialists, it probably won't be unhappy to facilitate any movement towards socialism in Russia.