So they wanted to destroy Earth and the Federation too....
Should we really be surprised that a Star Wars fanboi would want to do this?
But seriously, if that's what they were going to do why not make it a full reboot. Rather pointless to have such a galaxy shattering event happen and then go away to an alternate universe that will have nothing to do with it.
Well it's been used as a plot point in alt/future timeline stories since at least TNG. It's just a thing to do when you're trying to showing how bad bad has got for our heroes. Hell, Enterprise (not to bash on Enterprise) actually went full on Death Star.