That is nonsense. The reality is that most data simply is not sensitive, and there is no valid reason to encrypt it. I wouldn't use insecure FTP because credentials, but there's no good reason to encrypt your blog or something.
It's not so much about the data, but protecting your credentials for the server.
Jokes aside https is as much about privacy as is is about reducing the chance you receive data that has been tampered. You shouldn't only not use FTP because credentials but also because embedded malware you didn't put there yourself.
The bad news with FTP in particular is that only one request has to be intercepted and recorded to have persistent compromise, because the credentials are just a username and password transmitted in clear.