So I found this by googling for prometheusoperator.0.27.0
It looks like there was a 0.32.0 version added to OperatorHub 8 days ago, but maybe it's not published yet. https://github.com/operator-framework/community-operators/tree/master/upstream-community-operators/prometheus
So just create a new project my-prometheus, update metadata.namespace from 'placeholder' to 'my-prometheus'