Yeah, one of the issues with dynamis is that even on our sundered world, dynamis is a weak force.

Limit Breaks on the Source already have explanations from the lore book directly attributing them to aether. We use dynamis against Endsinger while in open space surrounded by concentrated dynamis.

One of the pitfalls with dynamis is that it was introduced very late in order to explain something that only happens in Endwalker. To me at least, there isn't much foreshadowing for dynamis before 6.0 and it feels like it was introduced to solve a problem they just created. It would've been the least they could have done to have something of an introduction to it in 5.4 and 5.5.

I personally don't hate it nor am I spiteful at it, but at least to me it's pretty obvious that it was invented long after most of the lore was already created and it was written in such a way that makes it difficult to reconcile it with past magical phenomena that have already been explained in detail.

Where dynamis has potential in the story is not in gunking up explanations of stuff we already "know" about, but in the future of the story. The dynamis genie is out of the bottle and now we are in a world that no longer has Zodiark's aetheric bubble or a Mothercrystal. There's potential for dynamis to affect new stories and new magic. It wouldn't surprise me if our level 100 abilities are explained with dynamis. That would be a nice way to cap off our classes before the inevitable level crunch.