The patch in [2] was added a bit over a month ago as a comment in a bug report about the GNU grep in the base system, so I don't think it's a good example of no one caring about bsdgrep bugs.
I FreeBSD developer requested that I added a report to that bug [1]. After adding the patch to the report, I also reported this to the list [2]. I have also tried to contact the maintainer of bsdgrep with no luck. At some point you just give up ;).
[1] https://lists.freebsd.org/pipermail/freebsd-questions/2016-J... [2] https://lists.freebsd.org/pipermail/freebsd-questions/2016-J...