>Do people really argue about variable names?
Of course they do. A program's code is mostly a graph of names; they can be cornerstones of its clarity, or sources of confusion and bugs.
The first thing I do when debugging is ensuring proper names, sometimes that's enough to make the bug obvious.
The greatest barrier to understanding is not lack of knowledge but incorrect knowledge. That's why good names matter. And naming things is hard, which is why it makes sense to comment on variable names in a review.