Take the attribute
app:layout_behavior="@string/appbar_scrolling_view_behavior"
off the RecyclerView and put it on the FrameLayout that you are trying to show under the Toolbar.
I've found that one important thing the scrolling view behavior does is to layout the component below the toolbar. Because the FrameLayout has a descendant that will scroll (RecyclerView), the CoordinatorLayout will get those scrolling events for moving the Toolbar.
One other thing to be aware of: That layout behavior will cause the FrameLayout height to be sized as if the Toolbar is already scrolled, and with the Toolbar fully displayed the entire view is simply pushed down so that the bottom of the view is below the bottom of the CoordinatorLayout.
This was a surprise to me. I was expecting the view to be dynamically resized as the toolbar is scrolled up and down. So if you have a scrolling component with a fixed component at the bottom of your view, you won't see that bottom component until you have fully scrolled the Toolbar.
So when I wanted to anchor a button at the bottom of the UI, I worked around this by putting the button at the bottom of the CoordinatorLayout (android:layout_gravity="bottom") and adding a bottom margin equal to the button's height to the view beneath the toolbar.