Again, with the "two separate hammers" analogy. They are the same hammer. You just can just use it for more than one purpose. How you use it, determines whether it's "good" or "bad".
What happens after you've destroyed "capitalist democracy" and replaced it with "socialist democracy"...and then someone learns how to exploit the system again? Do you destroy it all over again, and make a new one? Again? And then again, again? And then again, again, again?
At some point, would you not realize that it's not democracy that's flawed? Or would you just keep destroying it over and over again, expecting different results?