Though if you did it differently and the ligature was in a single-character width it would mess up alignment between users who are and aren't using the ligatures... probably a worse problem.
No, that's what happens in some ligature fonts: '=', '<=' and '===' all render a single character wide. It messes up alignment and drives me up the wall
Except no ligature font I’ve ever seen does that, because that’s a terrible idea and a mark against any specific font that does that, not against ligatures in general.
I tend to read horizontally and not vertically, so that hasn't been an issue for me. The column oriented code layouts I just find so eye-rolly but people like different things.
I do not like it when len('≡') == 3