For what it's worth, your main combo loses 20 potency and then bloodshower is stronger by 20 potency. Every time you AoE combo on 2 targets, you have a 50% chance to be 20 potency behind and a 50% chance to be even on potency. So yeah, Dancer lost 2 target AoE but it definitely wasn't unique. It's late so unless I am forgetting something, a very simple example is BRD. The basic ST combo is an effective 241 potency average and the AoE is an effective 144 per target, 47 potency superior at 2 targets (assuming they can both be hit with a 12y cone).

It IS pretty weird how they would change it in the middle of a patch and not really comment on it I suppose. But the scope of the change is pretty minimal. What's the overlap between "Caring about 10 potency" and "Fighting 2 targets"? I feel like the former is only applicable when doing high level content, which is generally not where you will find the latter.