Russia was of course incredibly backwards by European standards, but in the run-up to WW1 it was industrializing rapidly. Part of German strategic calculation was that if they waited too much longer after 1914 to fight a war with a modernizing Russia that they would lose.

Plus, it wasn't even the Communists who deposed the Czar. He was already gone after the February Revolution, 7 months before. The main contribution of the Communists to the cause was to spend the next two decades committing mass murder and achieving mass starvation.