Given the choice between "These icons look a bit garish in a subjective sense" and "what abstract art piece describes the Pages app" I'd rather have the one that's still useful. One benefit of skeuomorphism was the level of detail, that's fully been abandoned along with the affordances that brought.

Because it is literally the best way to design and everyone else is wrong. Look at actual HCI studies. There's exactly zero arguments for any kind of flat or minimalistic design outside of art, or if you want to make a statement.

The only reason it's used that it's cheaper and faster to make, is perfectly soulless not to make anyone upset, and it's trendy.

In the skeuomorphic era, people said, "This $object looks dumb."

In the post-skeuomorphic era, people said, "I have no idea what this is, what it does, or what it means."

Which is a better way to fail?