The main reason I'd want a bigger display is for more immersive content like videos, which are typically 16:9. On a Pixel Fold, you have all the added complexity of the fold to make the videos you watch on the train 1cm taller.
The iPhone Duo unfolds to be the same height as the iPhone Pro Max. Sounds like it has the exact same problem - a bunch of added complexity without a practical use for it.
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> Touch ID is integrated into the side button
Another major flaw with the foldable form factor - it's hard to distinguish holding the device e.g. to pocket it and holding the device to use it. My foldable does the smartphone equivalent of butt-dialing way more often than any phone I've had before because it likes to unlock itself when I'm putting it in my pocket