That's not true. The height of DC was the Jeantte Kahn post-Crisis era where editorial policed continuity much more tightly and in turn creators still were able to create great comics such as the O'Neil (editorial) era of Batman, the post-Crisis Superman and post-Crisis Wonder Woman. In contrast the Didio era didn't give a crap about continuity and it was a complete mess with only a handful of landmark titles, lot of mismanaged properties, lots of editorial micro-managing which persists to the current day and publishers trying to sabotage characters/books they didn't like. If anything DC's history shows that the belief in a shared universe (and thus continuity) helped it attain creative heights that the anti-continuity naysayers were never able to achieve despite all their efforts.