If you meant overarching themes shared by the series universally then...
Technology and progress that doesn't balance with the natural order is always evil or completely ineffectual when problems arise if they didn't cause the problems in the first place.
FFI - The Sky Tower which looks more like an orbiting satellite city in the Amano artwork is a dead city whose wondrous technology and machines fell easily to Tiamat. Even WarMech can be felled by simple knights and wizards. In the Dissidia retcon, the Lufenians are suggested to be the cause of Chaos' creation.
FFII - A large portion of the game's plot is dedicated to destroying the Empire's new Dreadnought Airship.
FFIII - The Ancients nearly destroyed the world by building a tower that flooded the world with light.
FFIV - The weaponization of airships allow Baron to become the most powerful country in the world and an easy choice for Golbez to use to gather the crystals. The game's ultimate villain is an alien who tries to use advanced weapons like the Giant of Bab-il to genocide the human race.
FFV - Cid's Crystal amplifiers ultimately cause his world's crystals to shatter and release ExDeath.
FFVI - The Empire's revival of Magitek and trying to use magic and technology together makes them over ambitious and leads the world to ruin. The fact Magitek resulted in Kefka becoming who he is doesn't help.
FFVII - Shin-Ra's Make factories are killing the planet when they're not blowing up and destroying cities. Shin-Ra dabbling in genetics also creates Sephiroth and gives him easy means to end the world.
FFVIII - Esthar weaponizes the Lunar Cry, their technology is only good enough to hold off Adel, and Odine's research into Ellone's powers gives Ultimecia the machine that allows her to destroy the past.
FFIX - Gaia's problems are caused by Terra's malfunction assimilation technology they use to give their race immortality. Also Kuja weaponizes Mist and Garland did create Kuja...
FFX - Technology proves to be useless in the face of Sin and well the party as well considering how often the Al Bhed failed to capture Yuna. While the Al Bhed are more positive tech junkies, it shousl also be pointed out that Bevelle was the other faction that used technology. The sequel plays this a bit straight since the game's doomsday device is an ancient Machina as powerful as Sin.
FFXI - Don't know too much about XI but as a former Bastok resident I can say that the industrialization capital of Vanadiel has a pretty bad rap since their city is polluting the region and causing the Beastment to fight back and all the racism caused by exploiting the Galka to help make the cities tech. I'm sure one of the expansions plays this one a bit more straight.
FFXII - The whole mess started when Cid began making Manufacted Nethicite. Not to mention the final showdown is in a giant airship that would make the Death Star proud.
FFXIII - Ignoring the fact the Fal'Cie are literally living machines, there is a contrast between Pulse and Cocoon where Pulse is violent but it's inhabitants feel better natured, whereas Cocoon is a floating city filled with assholes who are quick to kill anyone who threatens their safety.