Some of that is on AWS for initially making the defaults too open, but at the end of the day, S3 was doing what it was told.
Is there some case where S3 was locked down, and the data still leaked?
What? Their internal build system was comprised and the password for the FTP that hosted their software updates was "solarwinds123"
This had nothing to do with the cloud/a issue with a cloud provider.
Secrets in a public github repository is a leak, in the cloud.
Someone uploading their secrets to GitHub has nothing to do with the cloud and everything to do with the incompetence of the people using it.
"This is the clouds fault because one of our engineers made a mistake and 'the cloud' didn't stop them!" does not really hold up.