Because despite saying you're here for it, youre not here for it enough to be willing to take up arms to defend the person running the guillotine from the state violence capitalists will always use to defend capitalism.

I'm not really here for that either, but only because there aren't enough people who would join me to make it anything but a really complicated suicide method.

First you have to build the revolution. Then you'll have no choice but to fight the revolution. So you can vote for more of the same, or you can join an actual communist party and start helping to build the revolution. Hell, you can even do both. But one of those things is like praying for rain, and one is like picking up tools for the dirty, sweaty, unpleasant job of constricting an irrigation system.