A few points.
1) "Exclusivity" doesn't mean "holds on defense in arena". In 3+ years of this game's existence, it has never meant that. That's because it would contradict one of the major driving factors to battle in arena - the need to be active. That's why the AI is bad. That's why refreshes cost crystals. That's why there is a timer. That's why you can't set "defensive" teams that are different from the one you attack with - and why there's a cooldown timer after battle.
2) The "advantage" is on offense. DR + Malak can still easily crush on offense. And the fact that you have another strong Sith Empire character - who doesn't even have to be g12 or 7* to be viable even in top end arena. A character who frees up one of your other Sith to strengthen other teams in events like GA and TW.
3) In this game money has never been an automatic "I win" button - especially not on defense. So either many of those expressing frustration are "new" whales or they are not being completely honest. This situation isn't new or unprecedented.
