This snippet from providers/instance.rb demonstrate the issue:

@create_account = new_resource.create_account || Logstash.get_attribute_or_default(node, @name, 'create_account')

when new_resource.create_account is set to false, Logstash.get_attribute_or_default(node, @name, 'create_account') is getting invoked because this is how the || operator works.

I think that an explicit check if the property is nil should be used instead of the simplified check if it's truthy.