@underlap make sure the ligatures are on.
I used FiraCode for some time, but seeing JetBrains mono made things very obvious.
The font makes diffs particularly clear to read, because ligatures add some horizontal space.
Bottom line is: it's not about the sheriffs, it's about the ligatures...
@underlap set it up with vscode to try it out.
You should immediately see changes in many places around the code, the most notorious example could be the comparison, but there's a ton more (comments, member access etc).
Ligatures are typically narrower than individual characters, leading to improved readability for many of us; YMMV, it's okay if this doesn't change anything for you. It's just a matter of subjective experience and preference 😉