Exactly, Russia agreed to gurantee for a sovereign state, independent from both blocks. At the same time the agreement was made that NATO wouldn't expand Eastwards. Therefore the conditions under which the guarantee was given have changed and the initial agreements broken. That's exactly the cause of the problem.
American intervention with a coup, creating a hostile state at Russias border, which tried to cut off its Russian population and indoctrinate it against Russia. Militarisation of the Ukraine by the USA, plans for bringing Ukraine into NATO.
If those steps wouldn't have been taken by Ukraine, there wouldn't have been a war. Everybody can listen, carefully, to Mearsheimer, which is on point.