Well, their former chief editor Dan Didio is gone and yes, that makes a huge difference in the comics. Particularly, Didio hated the legacy aspect despite comic readers, especially those of DC, being fans of them, all because Didio thought having a history of the mantle being shared or passed on would force older characters to ”age” too much for his liking. So he removed all the Batgirl history save Barbara’s, made Barry the only Flash (despite Wally being far more popular among comic readers by this point), removed Donna Troy as Wonder Girl, etc. The Robins were left alone, likely too iconic for even Didio to think it wise to fuck with that, and since the 50’s Green Lantern has always been a shared position held by thousands across the universe so it didn’t matter if there were multiple human GLs. Anyway, most people who care about the comics hated this change, as it just removes a ton of long developed history and relationships just because heaven forbid some of the heroes be in their 30’s, or, “ew”, 40’s! Anything but that!
He also hated the heroes being in permanent happy romantic relationships (made doubly annoying that over at Marvel their chief editor hated Peter being married so he ended Peter and MJ’s marriage), so Clark and Lois were no longer a thing, Batman and Catwoman were breaking up at times, Batwoman’s engagement was ended, etc. Funny enough, Aquaman was immune to this, but that was likely due to Geoff Johns kickstarting the New 52 version of Aquaman, and Johns was one of the few people who seemed to get what he wanted (and Johns generally made decisions fans liked, save a few hiccups here or there) regardless of what Didio wanted.
Since DC Rebirth in 2016, Didio has pressured to have positive changes reversed (Wally West was brought back into continuity in Rebirth, but then the event Heroes in Crisis ruined his life, but that was soon retconned after fan outcry), but plenty have been fixed, such as the pre-New 52 Superman having returned and his marriage with Lois is still intact, Cassandra and Stephanie are now Batgirls, Donna Troy has returned, the original Teen Titans history was brought back into continuity, etc.
Like, he might seem like an easy scapegoat, but Didio truly did not get the fans and what they wanted. After the event Infinite Crisis, a 52-issue weekly series called 52 was made (no relation to New 52 which came years later) to go into detail of what happened in the year following Infinite Crisis (as all the series did a one year timeskip). Didio wanted it to explain stuff like, “hey, why is Superman wearing a different costume after the timeskip?” and stuff like that, but the four writers ended up having 52 focus on stories for more B/C-list heroes as they felt character-focused stories were more important than just explaining immaterial changes, and those stories were very well received by the fans. Didio was not happy, so later he pushed for another 52-issue series called Countdown to Final Crisis. He said it was, “52, but done right,” the fans read it….and to this day, it‘s widely considered by fans to be one of, if not the, worst comic series DC Comics ever released.
