This link displays it best:

https://www.techradar.com/news/android-p-only-has-space-for-...

In short there is a 4 notification icon limit now with the clock on the left, whether you have a notch or not. I often have a lot more than 4 notification icons up (esp since a couple are permanent from background apps) and the rest will just disappear under a dot-dot icon.

Wait. Everything has notch support, even if the device doesn't have a notch? That's odd, right? Given the notch is still an exception? Although they could make the status icons (top) tilt 90 degrees so they are usable from within landscape yet remain on their position

Yep, seems the compromises they have made for notches are global across all devices which to me is a UI mistake.