Good tools can improve your workflow for sure, but it's easy enough to keep a clean history with a handful of git commands. There are two main reasons people don't do so: 1. they don't know the commands yet or 2. they just don't care (and are in an environment where there's no incentive to care).

The kind of person who would try a tool like Magit and use it to discover git would have found a different route if Magit didn't exist. The type of person who doesn't care isn't going to learn something just because a tool is available.