I noticed that too, until I got good enough, I actually considered Guardians and Major Tests of Strength harder enemies than the Divine beast bosses. generally speaking, if you can beat a boss in one run with relative ease, its not hard enough. you should at least have some trouble with the boss...
for the amount of climbing that is required in the game, it seems to rain a lot. I feels like Miamoto was like: "don't forget that we can take away this climbing mechanic just as easily as we added it!"