In that case I would use it in DryRun mode and have it generate a report. Then look at the report and if it makes sense, fix the terraform or ArgoCD configuration.
More on report: https://gianlucam76.github.io/k8s-cleaner/reports/k8s-cleane...
More on report: https://gianlucam76.github.io/k8s-cleaner/reports/k8s-cleane...
Because, if you want to have a product to sell out of this (and I guess you do?), your n.1 client will be (IMO) big enterprises, which usually have a lot of cruft in their clusters and go after cost optimizations. But they also usually don't shove manifests in directly, they have at least one solution on top of it that takes care of resources lifecycle. So, IMO, if you want your product to be useful for those kind of customers, this is something that need to be improved.