Connected realms? Are you referring to the cross-realm dungeon finder? Because that’s all that Wrath added in that regard. And there were cross-realm bgs since Vanilla.
I think both those additions were terrible, btw. The last time I really cared about pvp was before patch 1.12 after which point pvp just became about killing and fighting alongside strangers. And the dungeon finder in Wrath destroyed the pve community that LFR finished off in the next expansion. But sadly it’ll be in Wrath since they just use the last patch and every system that existed at the end of the expansion. But out in the open world at least it’s just you and your fellow server players.