Oh yeah it's my game of the year easy, it's about as orthodox and hearful a classic golden era turn based jrpg as you can imagine, but with more complex story and world situations. It's a conclusion to 8 games worth of some of the best story and worldbuilding, also insane amount of content and character development. The NPCs in the world even have backstories and a metric ton of lines which get updated after every minor thing you do, so you wanna go around and talk to every npc in every area over and over and follow along with their lives as you go on doing quests and dealing with the main plot.
The main plot deals with politics in a world which up until about 80 years ago was a medieval society but due to a breakthrough in deciphering ancient magical technology has transitioned into a post-industrial society, so you have the dynamic of people who are still used to fighting as knights on horseback having to face a world where now tanks vastly outperform them. That of course brings political issues such as the nobility losing power to the commoners, and there's lots of trouble including mercenaries and expansionist wars and so on. There's a peacekeeping organization that's kinda like the UN which prioritizes the safety of the civilians in occasions of conflict which is your introduction to this world in the Sky games, and the cold steel games in particular deal with the most warmongering of nations which up until that point was the origin of conflict, it feels like you're playing on the side of the bad guys when you think about it before you play it, but then the nuance hits you, they show how it is trying to change its ways from within, forming the first class of cross-caste military students, and it follows their story trying to understand eachother and move their country to the future as they do.
Though if you wanna get into it you wanna start at the beginning because the games are a direct continuation of eachother, and in such a way where games end in MAJOR cliffhangers with nothing resolved, so it's the sort of thing where you wanna get into it with the intention of playing all of the games in the saga. This is kinda why this game is so enjoyable, it's concluding 4 games worth of events all by itself, also some other ones from the older entries in the saga on top of it too. That playtime you see there is just out of a single completionist run, no grinding or anything was done to get it up to that number, it just has that much stuff lol.
Also, it is highly recommended to go through the Trails in the Sky games first because they are the start of the saga and they set up the world, they're also excellent games in their own right and available on steam for pretty cheap by this point. You won't "need" need the knowledge of their games for the first couple of cold steel games since only 2 of the main characters play a major role in cold steel, but in cold steel 4 you have plot points from trails in the sky getting resolved, some 15 years later, so you can imagine the impact that that has.