It doesn't feel, to me at least, as much that aesthetic standards have changed in general as much as that they've changed on computers. I'm not certain why, but I'd guess it has to do with various things ranging from screen resolution to font availability to marketing.

On the other hand, the "fun" of fonts like San Francisco ('84) might have partially worn off as computers became more integrated into our lives.

Many currently popular web typefaces have been around for decades. Helvetica, Avenir, Franklin Gothic, Futura, etc.