How to uninstall this module ?

Closed [33293876] as duplicate of this issue.

Wondering if the module can do all of that during the uninstallation:
- set the default value of the base field definition or initial value to `NULL` or `` (or move this to the hook field info alter and implement one more hook update for this)
- set base field field definition as not required
- do base field definition update

Then, let the system purge the field.

What do you think?