Sometimes I need to reset part of a copr, setting up a new one is too much hassle and I usually need to keep some core packages inside (so I just kill the dependent packages).

So I do things like

<command> | xargs -I{} -- copr-cli delete-package coprname --name {}

That works but unfortunately copr-cli's feedback is far from ideal. It's a long list of
Package was successfully deleted.

that does not tell you which delete operation succeded

Please change it to

<package name> was successfully deleted.