I think the word is there will be. Just a bit early I guess. On GC1 and 2 it caused your empires morale to start tanking, but since morale was out, and is now in -- or is it -- I guess we will have to wait another build or two to see what they have planned for it.

You could still do things to get back on your feet. Like selling techs and other stuff to your less aggressive neighbours, or getting rid of some high-maintenance improvements.

The AI, on the other hand, had often big troubles recovering from this. Especially when it was losing population due to low approval, and tried to combat the loss of income by increasing the tax rate.

It appears maintenance on the planet itself has a large effect on approval. You could research the commerce branch as there are some decent wealth bonuses there. The other thing you can do is not build some things as that increases your maintenance. Instead, but your govern slider to wealth. Also, more population = more money. When taking over planets, look at expensive things maintenance wise to destroy. It seems the ai can spam tech capital wonders, social matrix, Hyperion buildings and likes to build cultural builds. Deleting those will save you a ton of cash, reduce your hit for wealth penalties on those planets and help turn your economy around.