They dived into it without first figuring out what exactly a foldable phone brings to a user as far as UX goes.
So far, Samsung and Huawei have both demonstrated that they aren't much more than a smartphone with larger screen real estate. But that's about it.
That shows how far behind they are from becoming the next Apple (THE player who everyone tries to copy). Although Apple isn't exactly doing its thing anymore.
IMO, they are doing the fold wrong. They both went with a 50/50 split. I don't really think it's a hardware limitation as flexible OLED demos clearly showed that the whole thing was flexible.
The only useful design that I can think of as a fucking geek would be 25:50:25 (yes, 2 folds).
When the phone is closed, it has a virtually notch/bezel-less main screen. The additional 2 folds basically provide area needed for controls (think Nintendo Switch), keyboard... etc. And when fully opened, it gives the perfect 21:9 for movie playback (landscape) or an extra long vertical reading experience that matches to the current app design components... only extending it.
Right now, the Samsung fold opens to a 4:3 screen ratio? all app needs their UI to be re-written to take advantage of that ratio. Or else you are left with black bars no matter which orientation you put it.