The game is pretty straightforward, but I meant following a guide more so for making a beeline for everything, so you don't waste time exploring the world map, traverse through dungeons in the most efficient way possible, etc. The kind of stuff that people naturally do when replaying a game they're already familiar with that a first-time player wouldn't do without guidance.

Like I said, I take my time and do optional things too, so people can definitely beat games quicker than my times. But even HowLongToBeat.com, which I find averages on the shorter side, such that I always expect to take longer, puts Final Fantasy IV as a 20+ hour game for the main story alone:

https://howlongtobeat.com/game?id=3499
https://howlongtobeat.com/game?id=3501
https://howlongtobeat.com/game?id=3500

And while 20-30 hours may be short compared to modern RPGs, it's pretty typical for 16-bit RPGs, so I wouldn't say RPGs that long really belong in a topic asking for the shortest turn-based RPGs, especially when Nz17 was asking for fewer than 10 hours.