The specific problems mentioned were all reasonably severe. The original post itself described a show-stopping bug:

    So my systems recently updated to rsync 3.4.3, and as soon as that happened my backup system - which does incremental backups using multiple --compare-dest= arguments - started to fail on anything but a full backup.

The second reply is similar:

    i wondered why my 3d printers were running like sh*t and at 100% cpu; turns out log2ram uses rsync.

Later in the comments, someone attempted to provide a list of issues that had been added: https://github.com/RsyncProject/rsync/issues/929#issuecommen.... The list included several failures to build or run rsync that appear to have resulted from broken backward compatibility. That seems reasonably severe. If intentional, I would have expected mention in the release notes about the removal of backwards compatibility, but none was made.

The issue comments already degraded into a lot of unnecessary vitriol even before the above mentioned comment and only gets worse from there, so I stopped. But, the fact remains that the whole issue started with a severe bug.

I applaud the attempt at dispassionately analyzing whether the recent LLM releases of rsync were normal or outliers as far as bugs are concerned, but I don't think you can do so properly without analyzing severity.

To keep such an analysis fair and contextually relevant, it would have to be extended to the previous 928 issues as well (of course filtering for bug reports). I don't see anyone doing such an analysis, I think because they don't expect they'd find it useful (at least not as the rage fuel that many are seeking); what they'd be more likely to find is that there is a similar severity-mix going all the way back to v1.0.0, because these things inevitably happen whether coding is done by human or machine.

"A lot of claims in the wider discussion have treated every recent bug report as if it had the same cause. That is not accurate. Some reports were regressions from recent security hardening, some were missing historical test coverage, some were older bugs found because rsync suddenly had more eyes on it (especially by AI that can find issues quickly) and some were packaging or environment-specific failures. A Co-authored-by line is not enough by itself to establish root cause." - https://github.com/RsyncProject/rsync/issues/929#issuecommen...