subscription name in step 1 command and step 2 command should be the same, or we can add an additional step before step 1 to get subscription name, and using variable <name> to replace subscriptionName in step 2 ans step 3 like 

step 1 : Get the subscription name for the Multiarch Tuning Operator by running the following command 
oc get subscription.operators.coreos.com 
Example output:
NAME                                  PACKAGE                     SOURCE             CHANNEL
openshift-multiarch-tuning-operator   multiarch-tuning-operator   redhat-operators   tech-preview

step 2: Get the currentCSV value for the Multiarch Tuning Operator by running the following command:
"oc get subscription.operators.coreos.com <name> -n <namespace> -o yaml | grep currentCSV"
Replace <name> with the subscription name like "openshift-multiarch-tuning-operator". Replace <namespace> with the name of the namespace where you want to uninstall the Multiarch Tuning Operator.

step 3...

chapter link: https://docs.openshift.com/container-platform/4.16/post_installation_configuration/configuring-multi-arch-compute-machines/multiarch-tuning-operator.html#multi-architecture-uninstalling-using-cli_multiarch-tuning-operator

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