Not sure what you mean. A blog POST is much shorter than a Hub but that's only one post on a big blog.
A blog needs regular updating with blog posts, so you need a lot of material to fill a whole blog - far more than for one or two Hubs!
Each Hub stands on its own, so you can write Hubs about all kinds of different subjects and stand a chance of making money.
To make money with a blog, you need to pick one subject. If you write about anything and everything (or worse, about yourself), it won't work.