In the front end it's possible to delete the default for the extendedEmailPublisher-Plugin:

Editable Email Notification > Advanced Settings > Triggers > any > "Send To"
....
The recipients of "send To" can be deleted so it's possible to add custom recipients in recipient list.

Using jobdsl plugin leaving sendTo empty or setting to "null" outputs custom behavior recipients list which is not the desired behavior.
An empty String is not allowed.

The configure block to achieve the desired output for 4 different triggers is quite ugly.