If this wasn't a discussion about monospace fonts, I might be inclined to agree with you. However, I kinda agree with the detractors here; ligatures objectively defeat the purpose of equally-spaced characters. The purpose of monospace fonts is to provide definitive clarity where sans and serif fonts fail to do so. In the world of programming, maintaining that consistency is essential. Having one symbol span several spaces undermines that clarity, you may as well be reading your code with Helvetica at that point. I understand that programming is a career path filled with creature comforts and obscure little things that make you happy; I even enjoy the warp cursor (gasp!) in VS Code, which definitely doesn't contribute to clarity. Let's stop treating ligatures like a direct upgrade over normally printed monospace, though. It's an option, one that shouldn't come enabled by default but one that should be available for people who want them for whatever reason.
Monospace fonts are used mainly because vertical alignment is desirable, and because characters such as ! and . are too narrow to easily read in proportional fonts. Monospace, then, improves clarity. Turning a => into a ⇒ does not affect the vertical alignment nor make anything too narrow to read. It just turns a combination of symbols into its semantic meaning. It allows you to parse a meaningful glyph rather than using a hacky workaround to represent meaning via ascii. This is also the point of emojis: (-_-) is fine, but most people find <expressionless face emoji> to be more clear as to the meaning. Nobody is getting confused about what these ligatures mean. They installed the fonts and selected the fonts in their IDE; they have already been coding; they are not going to see ⇒ where a => used to be and have a brain meltdown.
