it is a bit too early to tell how any civilization for Season 2 will have developed technology wise. As of now mostly everything is a assumption since Season 2 is about exploring the Unknown regions of FF14 that we have little amount of lore about such as the remaining shards, the New World (still mostly unexplored certain civilizations have yet to make contact with Eorzea exploration teams yet), and etc.
Garlean Empire may not be the only civilization that developed into modern day technology in the Source and we still know very little about the remaining shard to be certain how their civilizations have developed both magic and science wise. The smallest of details in a civilizations development can greatly affect what path they follow in technology advancement and how fast they advance after all.
We also have to keep in mind Garlean Empire did establish influence in regions beyond current regions as well so their technology advancements may have also affected certain regions we have yet to explore located in the Unknown Regions we will go to once we can enter the New World which we know had been under Garlean control far longer than the regions we currently have access to. This can lead to a new civilization that have intergrated Garlean technology into their own society more than the current civilizations we can go to due to longer exposure to Garlean control over their region before Garlemald fell.
Only thing certain is that we will eventually get there at some point in Season 2 due to the Spoilers that Emet gave us at the end of Endwalker. Emet's message is clear being that we should prepare for both the unexpected and the expected when it comes to the new civilizations we will explore in Season 2 for both on the Source and the remaining Shards.