Are you referring to this ZoL issue https://github.com/zfsonlinux/zfs/issues/8259 https://www.phoronix.com/scan.php?page=news_item&px=ZFS-On-L... ?
> You can use FreeBSD, they are happy to provide
I'd stop at that.
What's going on here is that people on the internet are asking Greg K-H to do extra work and his reply is that he doesn't care to.
If anything what is childish is random internet users thinking that they are entitled to Linux dev's time and work.
That really isn't "what's going on here." The "extra work" is changing one or two lines from containing EXPORT_SYMBOL_GPL to EXPORT_SYMBOL and possibly moving them to a different place.
If you read through the email thread [1] linked in another comment, you'll see something completely different is being argued and discussed.