It's obviously absurd - he didn't have to attack Ukraine and ruin relations with the West; but by distracting with cherry-picked historical facts it creates an air of deep knowledge and sophistication. He chose to perpetuate the cycle of confrontation.
It is not a 100% honest belief, as the Kremlin has a long tradition of falsifying history to fit its agenda. And given the importance of "history", controlling the past is an attempt to control the present and future. One classic example of how history is changed to fit narratives is Zhukov's memoirs. You would think they wouldn't change much, but they have 12 editions that contradict each other. Each edition claims that his daughter has found new sheets of paper or that they've simply restored what the previous editors had removed.
It is really frustrating how uncritically these views of history are accepted, critical thinking out of the window. Western historians are more often worse than reading Russian historians as the former stick to extremely biased 'official sources'.
In the Groundhog Day eventually the main character learns something and breaks out the cycle. I wonder how many times it has to repeat for that to happen in our case, but I know for sure no rethinking of the past and future is possible under Putin.
From Zhukov's analysis most of historical facts are true but conclusions are wrong.
Nationalities are always changing, growing, evolving. If we look sufficiently far then Slavs and Germans should be counted as cousins