This is a good point. If everything is canon or everything counts, like some people at DC have been saying, what do they do with things like Batman, Superman, or even Robin being created in the Golden Age? Do they have any memory of those original Golden Age stories back when they happened, or are those stories just going to be pushed up to being Silver Age stories now? If so then that is a big shift in how the universe unfolded chronologically if that is their gold of this whole endeavor.
I'm not really interested in 5G but how they decide certain things I am curious about. Like how old will all the Robins be? That is a good example of how the different generations will be spread out. Dick should be much, much older than the rest of them while Jason and Tim should be very close in age if they are going by chronological age, but I don't know if DC will do that.