Is Sekiro worth $15?

I have never played this game before, but my friend sells it for $15 on Xbox. It's the normal version, not GOTY (I have no idea if there is a difference or if they are the same game, or should I only buy the one that says GOTY), but is that a good deal? Or does it get cheaper on Steam/Xbox sale?

I have looked up gameplay, and it looks pretty fun, but I am not sure if it gets boring or if it has any massive issues that I didn't see in the online gameplay.