I have never really liked any of the other popular coding fonts and it really comes down to one thing: They are all stupid sans-serif fonts.
I have found, ever since displays grew out of the garbage 100 dpi age, that serif fonts are vastly more enjoyable to look at and easier to quickly visually discern.
As a result, Iosevka Slab is basically the only code-optimized font I can even consider.
Beyond that, I prefer a narrower font for monospace text. Monospace is already such an awful layout for readability, but, making it narrower at least helps reduce the horizontal scan range without imposing insane limits like 72 character lines.
So, those are my reasons anyway.