I got to buy a flip and a fold for QA purposes for work. I test drove them for a few days before handing them over.
I daily drive an s24 ultra so I'm a fan of big phones already.
The use case for the fold is for anything where you would rather have a tablet. Some people would rather consume media on a bigger device. The real downside to me with the fold was the thickness while folded. It was uncomfortably thick in my pocket. And then of course there's the inability to have any decent protection on the phone, and the lack of water resistance.
Now the flip on the other hand, I really enjoyed that device. It opened up to the same size as a decently large phone, you could fold it up and throw it in your pocket, It was protected.
They're both too damn expensive. You could buy the biggest baddest flagship phones with the most beautiful screens and cameras for the same price as something that just folds up a little smaller in your pocket.
Back when I came into the office every day, it was a 45-minute commute. At least one day every week, I had no active memory of getting from the north side of the beltway to my house (about 20-25 minutes). I'd reach this point, and it was like someone flipped a switch, and I became aware that I existed.
I've done this with Audio Books. I've listened to 2-3 chapters, and they'll mention an assassin; Brain goes, wait, assassin? WHAT ASSASSIN? I start rolling back find out I completely tuned out 20 minutes of the story.