Pixel density isn't the problem, physical size is. Phone screens are small and many people have poor vision. Some even scale up the contents of their browser 25

Pixel density isn't the problem, physical size is. Phone screens are small and many people have poor vision. Some even scale up the contents of their browser 25% or 50% or even 100%. The more text you have, the more difficult it is to ensure a usable UI on small screens, let alone a good one. Don't be upset about the use of symbols instead of text, but about the use of bad symbols. Nobody needs the "play" button on a video widget to say "play" - they know what the right-facing triangle means. (Ironic because I don't know if it makes geometric sense to even say the triangle has a facing, but as a symbol it's well understood.)