That's not how their post comes across to me.
I think they've been refining the game but I don't think it's changed the tone or target audience. They've never aimed to compete against any specific game and just want to do their own thing. 1.0 being the exception, but we saw how that turned out.
ARR was just a rush to get something that was playable out the door. A lot of the old plot elements from the OG 1.0 before 1.2 were changed or dropped altogether and it became a "Final Fantasy theme park" with much more fantastical design elements and a pretty black and white plot. The Scions and Minfilia continued their roles from 1.0 to be our story guides.
HW refined that a bit more with a political storyline overlapping fighting dragons in a war that was caused by the people of the city the expansion takes place in. HW also is where they seemed to start to build the classic "FF party" during our journey to Hraesvelgr with Estinien, Ysayle, and Alphinaud.
SB took that party concept again with Alisae and Lyse following us on our adventurers after thinning out the cast by removing the extraneous Scion, Papalymo and before writing Lyse out to do, whatever role she is now so that the cast herd is more manageable.
ShB, now flush with all that successful MMO cash took the thinned out herd of characters and was able to concentrate more deeply on them for a longer period of time since the expansion story was longer than the first few. Each of the characters got focus during their own parts of the story before we brought them all together. The story also came back to the grey-morality plotline that SB skipped over.
I just see EW as an extension of what they were doing in ShB. We have these set characters now, and we focus on them and since they're altogether for large swaths of the expansion or at least come together at the end of every arc, we can have them interact with each other.
I don't see a lot of what's being complained about as a "specifically designated" tone shift, but just the director and the writers building on what they had until they found something they liked. It's also why I never figured they would ever write Hydaelyn/Venat as a bad character. They definitely dropped the ball on writing her motivations but the intention has from the very beginning for her to be a character you're supposed to support. And they gave nuance to the Ascians but when they were written back in ARR as "I don't know what their goal is but lets just have them do bad stuff", they were never meant to be the characters that would ultimately be fully vindicated and "win". Especially since their version of winning deletes the whole game map.