Thanks to endlessly regurgitated conservative propaganda, we have the myth of Reagan bringing down the Soviet Union....among other things he had little or nothing to do with!
Best theory I've heard on what ended communism in Russia is that it started with top Communist Party officials wanting to end it and become rich capitalists, like their western counterparts. So, they engineered the fire sale of state assets in Russia, Ukraine, Belarus, Kazakhstan etc. and became billionaires.
BTW, if it was all about communism, why has the US been engaged in a strategy to keep advancing NATO and encircle Russia with hostile forces? Looks like we are closer to full scale war between US and Russia than we ever were at the height of the Cold War, because capitalist Russia is using Syria to showcase their weapons industries and compete with America's #1 export! So much for all that bull**** 25 years ago about how "free" markets would end wars and reduce the risks of major military confrontations.