Yeah… I’m only surprised that they shifted tactics so quickly. Fear, Unrest, and Doubt are the key tactics in Russian Disinfo campaigns. There’s an old axiom: If someone is trying to make you feel strongly about something, then they are trying to sell you something. In this case, OP Is trying to piss people off in order to convince them of propaganda and Russian talking points.
The simplest answer is that they are getting it from Russian Propagandists. They repeat it because it riles their base and gets them engagement.