Answers from my (user and frequent bug reporter) view:
1. abrt/libreport reports way too much data. There is no need to report my hostname to
Fedora/RedHat infrastructure. Same for UID, PID, username, time, environ, …
2. abrt/libreport leaks much sensitive data. This includes paths in my home directory, but
also other data listed above
So it is about privacy. I have reported enough bug reports containing information I
didn't want to get published so I learned to use the private flag whenever I'm not
sure I might leak information. If you want me to not use this feature any more, please
make libreport does its job at filtering private data. See
https://github.com/abrt/libreport/issues/353 for a bug report.