I'll never understand fans who think the original timeline was overwritten. I think some people forget that this is all just made up. The rules are whatever the storytellers want them to be. And no storyteller is going to want to say that the Star Trek we've been fans of for 45 years has somehow "ceased to exist." The whole reason Abrams & co. created the alternate timeline in the first place was because they wanted to leave the old timeline intact and unaltered. (Also because they're using plausible, informed physics in which different timelines always coexist rather than overwriting each other.)
Also, remember the TNG episode where Worf got out of sync with the universe and kept bouncing around to different universes. Then we saw a number of Enterprise
s from different universes appearing together. So what's to say that something like what happened in Star Trek XI
didn't cause any of those to come into being?