In Haskell I have different colors for the comments, keywords, and literals. That's it. Anything more is not helpful.
It's baffling to me to look at source on Github and see a screen full of comments, greyed out.
The code is what is hard to read, comments are easy to read. I want help focusing on the code, I don't mind if the highlight structure doesn't help me read the comments as they are more than easy to read already.
At best, they are a statement that, at the time they were last edited, the author believed their stated facts were true, or might become so, plenty are aspirational, "this is what this function or change to it, which I've not yet written, will do".
He might have been wrong, or the code might have changed without updating the comment, the actual running code is the only truth.
But generally commit messages, descriptive symbols, simple logic, short functions, and unit tests are better.