Am I missing something?

I made a CC Julius with massive buff/debuff stacking. I'm not sure how their specials are doing so little damage. I know his Def & Res is pretty massive in my examples, but R.Astra should at least be doing...more. And what about Moonbow? It's scaling off of Julius' 57 Res total. That's 17 Dmg. I thought Moonbow & Luna did damage scaling off of enemy defenses, rather than adding to Dmg total.

Calculations:

Julius is buff-stacked up to 42 Def in the first image. Then, you add the Atk Ploy and Loptous debuffs, which make up to 11. Essentially, about 53 Def. The Ayra in the example was running Distant Counter + Quickened Pulse...then I remember she's using a refined Slayer, basically putting her at about -9 Atk before battle. If we lowball it to being R.Astra off of 40 Spd, it adds up to 7... that makes a lot more sense.

Reinhardt

I ran this on two different calculator + personal maths, and I don't see how Moonbow barely works. The example is a 51 Atk Reinhardt when initiating. -Atk Reinhardt with +3 Atk Seal is starting off at 41 Atk. Debuff puts that at 35, with an Hone to 39. Death Blow puts it at 45, and Triangle Advantage adds up to 54 Atk, leaving him at -3 Atk...if Moonbow scales to 17 Dmg, that should be 14 Dmg total. If you factor in Death Blow after the Triangle Advantage, it gets a lot closer and he should be doing 6 Dmg total.