its not the exterior hinge & movement component that will be scrapped or changed. the sub-screen internals will be modified to allow the foldable screen to (bend) at a much wider radius than previous foldable devices. a side view cutaway shows how the screen will look more like a "waterdrop" inside the device when folded. this will reduce the visible crease.
According to a new report, the Galaxy Z Fold4 and Galaxy Z Flip4 will finally adopt the increasingly popular waterdrop hinge design seen on foldables like the Xiaomi Mix Fold 2 and OPPO Find N2 series. That design choice will not come at the cost of ingress protection either, with both Samsung foldables seemingly set to retain their IPX8 ratings.