To show icons to the 99.5% of people who use the web with Javascript? Even Font Awesome suggests people go this route today.
I noticed the default free CDN option was JS when version 5 of FA came out, but now the default is font based:
https://fontawesome.com/get-started
Note the tab order, it's Font | Js | Desktop | Advanced.
It used to start with JS, so I think you may be wrong on this point, even if they "recommend" it in their docs, their defaults argue otherwise.
To show icons to the 99.5% of people who use the web with Javascript? Even Font Awesome suggests people go this route today.