The history panel seems to be limited to 5 actions. Additionally, with the latest update (20.2), if you access the history panel at all, it overtakes the Ctrl+Z / Ctrl+Shift+Z function for undo/redo as it has worked in the past.

When the history panel is opened, it selects the most recent action. Even if the panel is closed, whatever is done after this point erases all the other actions, so that you are left with "open" as the previous step. Edit>Undo (Ctrl+Z) is disabled, and you can no longer undo work.

Additionally, steps will sometimes combine themselves without any user action. (i.e. while documenting this, in between image 3-4 no action was taken except to switch between InDesign and the screen capture program). Switching in/out of InDesign erases the ability to undo work.

If you type 6-7 characters, you can no longer undo anything prior to that. Open the history window, select a step, then place something.... undo is now limited to the place action; all other history steps are erased (as well as Ctrl+Z undo/redo steps).

This is a huge step in the wrong direction.

There are seemingly no settings related to history (unlike in Photoshop where a number of steps can be preserved). Iteration/layout experimentation is critical in InDesign and this update removes the ability to do that without incessantly creating a snapshot every time you do something or type more than a few characters.