> Users are not interacting with a screenshot.

Yes, they are. You seem want a distressed user to aimlessly wonder though the UI trying to learn how every object behaves. That's not only unreasonable, on this case it's mean.

You would be correct if it was a game.

> You seem want ...

I agree with you more than the GP, but this isn't a good way to structure a rebuttal.

Only if you assume a fall would be the first encounter with this UI element on an Apple device, that is extremely unlikely.

Though a return to a little bit of depth in interface design would help. Even plain tappable buttons often have zero affordance these days.

> If you try to tap the slider it will slide a little to the right and fall back to indicate it’s a slider.

People can’t interpret that kind of nonverbal/abstract cues. It’s quite an inner circle thing of nerds that those seem ultra obvious.

Apple's whole thing is "computers for non nerds".

Nerds would type SOS at a command prompt.

That's why Jobs-era iPhone always visually AND verbally instructed "[→] slide to unlock", where nowadays it's just a ───── at the bottom that are supposed to be extremely discoverable and immediately obvious and magnificently intuitive.