Well now I'm confused because it says that "Dynamis is a far weaker form of energy, and is almost completely nullified by Aether in equal quantities." They don't interact with each other so to speak but they can cancel each other out according to the game. Here's a link to the website that I'm getting my information from
https://ffxiv.consolegameswiki.com/wiki/Dynamis
Theoretically this means that a ton of aether could blast meteion away because dynamis can be completely nullified and cancelled out by aether even in equal quantities. Also you raise another good point. Hydaelyn, using the logic that aether nullifies dynamis, and if she was able to, could've gone out into space and killed meteion too. That would've made one hell of a cutscene.