You would have to infer the intent of the code. One example, from a small project I'm working on:

    $ find . -name "*.go" | xargs grep 'if err !=' | wc -l   
     242
    $ find . -name "*.go" | xargs grep 'if err ==' | wc -l
      12

So about 5% of the error checking code is about handling the edge cases, where we are very much interested in what the error actually is, and need to handle those conditions carefully.

If you discard that as "error handling noise", you're in for a bug. Which is, by the way, perhaps the worst side-effect of verbose, repetitive error handling.

Apropos syntax highlighting: many themes in regular use (certainly most of the defaults) choose a low-contrast color for the comments. The comments are often the most important part of the code.