Ishikawa isn't the only writer so I don't understand why people feel the need to pin everything on her.
Banri Oda was on the writing credit alongside Maehiro from ARR through 3.0 which was Maehiro's last writing credit, and continued to be on it from 3.1-now alongside Ishikawa. Ishikawa was main scenario writer in 3.2, 3.4, and all of SB and ShB (Oda and Ishikawa shared this title for both expansions) so I don't know why your cutoff is pre-ShB and post-ShB. Yoshi-P has had full and direct oversight in how the game is run and the story points since the beginning. Maehiro leaving after 3.0 to XVI doesn't immediately make the game change in tone since he wasn't writing every last story and he was working alongside Banri Oda and Yoshi-P the whole time anyway. Plus, most of the lore originates from Oda himself and not the other writers and he's still here.
As I said in the other thread going on for Endwalker's story, HW's tone is different because Yoshi-P specifically called for it to be written as "dark fantasy". Knowing this, you can look at ARR/ShB and see how they were written specifically in the sub-genre "heroic fantasy", SB is clearly a war story, and EW is a mix of them all with a dash of sci-fi.
Matsuno wasn't "chased off" by negative reception by the English lore forums or people who like JRPGs, it was received negatively in Japan but they didn't go much more into it. Yoshi-P and Matsuno even had an interview last year or the year before after Bozja to talk about it and possible post-Bozja plans but people seem to ignore it for the "drama".
Garlemald being nuked off-screen by their own hand is partly a consequence of the 1.0 writers making them too strong imo. Other than deus ex machina there's not really a chance for Eorzea's military to do more than just defend when they have magic, bows and arrows, swords, and muskets against a fully mechanized and modern military with magitek. Even Ghimlyt Dark required WoL to show up.
The other reason Garlemald is what it is, is because in an interview Yoshi-P said that if we went in guns blazing, we'd just continue to see Garlemald and the Garleans as faceless mooks to kill instead of the average people and their stories and that had an effect on the state of the zone.
If you want someone to blame for "emotional spectacle" you might want to look at the creative director more than anyone else.