For the most part, Eorzea reflects the early modern period in terms of technology: firearms, plate armor, lensing, large ocean vessels, humoral theory of medicine, etc. There's still some schizo tech thanks to Garleans and Allagans, and of course the fantasy setting has things like crystals, glamours, and enchantments that augment technology, but for the most part the setting reflects 15th-18th century real-world history.