I don't think the writing of any FFXIV expansion is particularly mature and I don't think its really trying to be, it's visually pleasing fantasy locales with some wars sprinkled in. Dawntrail is just so bland that characters saying "shite" is fiery in comparison.
I do think Stormblood tries to veer into a 'darker' tone, as it takes a more granular look at war, rather than it just being something from the MCU where all combatants line up against each other and pew pew.
The game steps a bit into oppressor and oppression, and what people will act and think like when under occupation. It's not some super deep story, but it does go a little further than your average JRPG/MMO story and it is more front and center than it typically tends to be in other games.
A good example is the
'I don't eat pork' exchange in World of Warcraft, where it is basically background stuff.
Unfortunately, the general XIV audience is retarded and Stormblood was/is seen as a 'meh' expansion, so that sort of exploration was scrapped.
If just because some sperg might actually do this, who the fuck ever gushed about ARR having a great story and why do we keep sperging about that as a relevant note?
There is a retard mentor (ah, but I repeat myself) I know of who swears up and down that ARR is an amazingly good story and is vitally important for the super awesome MSQ that he comes down hard on anyone daring to speak ill of ARR's numerous faults.
I think
@Sunflower Samurai is pretty close to the mark -- I think a lot of people are conflating the narrative praise XIV got in
Heavensward with the developer praise XIV got for ARR (honestly, XIV's turnaround should be used as a case study for developers as it was a Dragon Age: Veilguard-tier disaster for Square) because, let's face it, most players didn't pick up the game Day 1 of ARR (or even Heavensward.)