I didn't find a single video about this so I thought I'd create one.
The two types of AOE4 Camera Modes (Classic and Panoramic) shown in a short clip.
Switching between them requires for you to load up another match so you cannot change those during a match/game. You don't need to restart the whole game however.
The Panoramic camera mode was added later on in the game and basically just seems to let you zoom out more whilst the Classic camera mode is set at a lower angle and not as much "directly above" like the Panoramic one.
In the end it all comes down to preference but with Panoramic you will effectively see more on the screen at once, although things might look smaller. You can, however, always use mousewheel zoom if needed.