This is apparently due to the 3D sensing module in the iPhone 13 that will be smaller than previous models, which is why Apple will be able to reduce the size of the notch. However, at this point in time it is unclear how much smaller the new notch will be, it should still be an improvement all the same.
In fact, this corroborates an earlier claim by leakster Ice Universe who claimed that Apple will reduce the size of the notch in 2021. That being said, it is unclear when Apple will ditch the notch for good. Right now the problem with losing the notch is trying to fit a camera under the display of a phone without the display interfering with the front-facing camera.
ZTE has attempted such a design but given that we’ve yet to try the camera out for ourselves, we can’t really speak to its quality. Even Samsung is said to be struggling to find a solution because leaked renders of the Galaxy S21 show that the hole-punch cutout will continue to remain part of the phone’s design.