How can you set a default blueprint?
Any supported Clarity release.
In order to set a default blueprint, you need to go to the Modern UX Administration > Blueprints, then in the grid, select the blueprint that you would like to set as default and right click it and select 'Make default'.
You cannot set a default attribute value for blueprint in Classic (i.e.: by going to Classic Administration > Studio > Objects > [object] > Attributes > Blueprint > Default).
This means that when you create a new object instance, it will not get a default value in the blueprint attribute. Instead, if the instance does not have any blueprint value set (that overrides the default), it will open the blueprint that is set to the default for that object.
You can see this by testing this example scenario:
You can set the blueprint while using XOG so that the Blueprint ID has a value in case that you want to override the current default blueprint. Note that if this does not have a value, if you change the default blueprint at a later stage, this will also be applied to that instance with blank Blueprint ID.