Premades - are 2-5 players who Que up together in bgs to try to get wins! This is not only acceptable but also encouraged as wow is a massive multi online player game.
Que syncher - they have discord communities and exploit the Que system to gain access to bgs with multiple pre-made groups at once to gain overwhelming odds vs regular Que users. They also use addons and other nefarious ways to manipulate the Que system such as Que dodging.
Que synching and the communities who do it have ruined epic bgs. Blizz hasn’t and probably won’t do anything to stop it….but don’t confuse premades with que synchers. One is friendly social gaming and the other is exploitive, manipulating game play. Best we can do is ensure that anyone who Que synchs is reminded of their unsportsmanlike and cheating game play.