At Samsung's developer conference, the Korean colossus showed off a new foldable form factor concept. The concept video showed a foldable display that opened vertically, just like a classic flip phone. This design seems to be gaining traction; if Motorola's rumored RAZR foldable is any metric to go by, clamshell foldables may be the future for flexible display phones.
https://www.notebookcheck.net/Samsung-shows-off-clamshell-styled-foldable-phone-concept.440563.0.html