I believe I spent around 100 hours with the game and I didn't even do half the shrines!

The bosses weren't all that tough for me except for Thunderblight Ganon with his insanely quick movement speed, but the game itself can be crazy. Especially some of the enemies that are just as strong as bosses and are just...walking around in the world. Have you played Hard Mode yet? It takes the difficulty up to eleven. The very first enemy in the game is almost impossible to defeat without searching for much better weapons first!