I'd put that down to the writers not being particularly great at writing antagonists intelligently. They always fall back on the same increasingly stale tropes and overly contrived plot devices to the point where even minor characters are clad in ridiculous amounts of plot armour.

The Witcher 3 is but one example of compelling writing on that front as far as I'm concerned. There's two incredibly powerful foes that cannot be confronted directly and instead need to be dealt with through diplomacy or trickery - and even then, they're not killed or overpowered.

FFXIV struggles immensely with the idea of not only allowing the antagonists a meaningful victory every now and then but also not having them conveniently have a breakdown right before they're set to become an opponent to do battle with.