It looks like the two packages that were bumped forward are ones where the changes were very minimal (it's not obvious why errno even bumped their 'major' version, and udev seem to do it on every release even when backwards compatible). Also errno 0.4 doesn't seem to exist, so I think that's a typo.
(There is a somewhat frustrating trend in rust packages for them to sit on 0.x versions for a very long time, even if they're fairly heavily used in the ecosystem and pretty stable in practice)
From what the author of bcachefs is saying, the forward moves were not a problem, it was moving bindgen backwards which broke the build, meaning the packaged version of bcachefs-tools stayed very out of date, causing him to get bug reports for known and fixed fairly serious bugs (ones which rendered machines unbootable).
(There is a somewhat frustrating trend in rust packages for them to sit on 0.x versions for a very long time, even if they're fairly heavily used in the ecosystem and pretty stable in practice)
From what the author of bcachefs is saying, the forward moves were not a problem, it was moving bindgen backwards which broke the build, meaning the packaged version of bcachefs-tools stayed very out of date, causing him to get bug reports for known and fixed fairly serious bugs (ones which rendered machines unbootable).