I like to think that blender is for more advanced modeling and sketchup is for beginner modeling..
well sketchup can't do the more advanced aspects of 3d art like animation or UV mapping so this is objectively true
not necessarily: they fill different functions. sketchup was designed around modeling visually, as well as a tool to construct models for google earth, so its better for converting real images to models and modeling buildings/large stuff in general. blender is designed more around general modeling and animation, a free version of maya and 3dsmax, so it doesnt fare as well when doing terrain and replicating irl buildings exactly