I don't think any designer has cared about that in the last 30 years. Perhaps not ever.
Arial is popular because people see it and say "good enough!".
Here's my anecdotal, completely unfounded theory.
Serif fonts were used in print media for ages but when computers came around sans serif became significantly more popular as no longer was there the legibility concern with dodgy pigment applicators etc.
People started to switch to sans serif fonts more and more and would seek out an alternative to the widely defaulted Times New Roman in early days. They'd open the alphebetically sorted fonts list and what did they see at the top?
Arial.
Keep in mind, when personal computing started out, we didn't have a ton of fonts packaged with the system to start with. Just a handful. Arial has pretty much always been there.
its the default
> I don't think any designer has cared about that in the last 30 years. Perhaps not ever.
Not true at all. For instance, Arial was/is typically used as the fallback font for Windows users visiting a website that relied on system sans-serif fonts, while Helvetica shipped with OSX and would be prioritized for those lucky users.
Arial would be chosen by Windows users as good enough because they were already locked in a prison of bad design and terrible typeface rendering anyway, and didn't have other sensible options installed by default.