I recently rediscovered that I can do GUI menu things on the keyboard in apps like VLC. Feels like a magic trick -- the best of both worlds. Was it the move to phones that did it? Or did most people not use alt shortcuts?

My memory is hazy but the heydey of underlined shortcuts was in the era when not everyone used a mouse, if I remember right - support was strong in e.g Windows 3.1 (dating myself a bit here) and got worse from Windows 95 onwards...

Some keyboard apps will input those shortcut combos. Many work on phones. I found out when using a Bluetooth keyboard one day for some emergency doxument create when I got stuck with both a deadline and a dead laptop.