I don't really understand the backlash against dynamis, but maybe it's the physics analogy, or that even in the fantasy I read with hard magic systems (Brandon Sanderson comes to mind), they don't tie every single magical element to one system or force, even if that's the one that gets the most detail- but having everything in XIV being handwaved as 'aether' was deeply unsatisfying and came across as lackluster undeveloped writing. Having a second named magical force that operates in ways that can be both opposing and complimentary, and isn't a complete handwave mystery but has some room for the writers to flesh it out - and that it is regulated to being weaker except in very specific circumstances- only comes across as a bonus to me. Sure, I understand the fear that everything and every enemy going forward is going to be explained via dynamis instead of aether because here's our new hot plot macguffin - but it's yet to be a factor in the Pandaemonion raids, and it feels like a useful additive retcon instead of subtractive.

It certainly made Omega Raid less cheesy.