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The best way to achieve removal of resources from the blueprints is to group the artifacts (ARM template which deploys resources, policy and role assignment) under a resource group. In this case, when you would like to remove the deployed artifacts, you would only have to delete the resource group and the contained resources will be removed. You may refer to this link for a quick overview of blueprints and demo.
edit 01/04/2022:
The functionality to be able to remove resources will be available through the new Deployment Stacks resource type, which is what Blueprints are eventually going to use under the covers.
You can get more information about it from this video link.
The QnA thread here also has some additional information that you may review.
Please let me know if you have any question.
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