Further update:
For clarification, the problem is invoked by pressing the “insert” key to switch to “showcase” camera (I’m using MSFS 2020 keyboard profile.
Viewing aircraft exterior shows sea and sky when overland returns when the sim next started.
The wake turbulence issue has not returned.
Selecting the showcase camera on the menu bar only needs to be done once to fix it. However the problem will return at the next sim start.