Not really, the upstream Linux kernel community is not big on milestone tracking and bug reports 
The initial set were ext4, xfs and vfat which were included in Linux 5.12, btrfs looks in line to make it to 5.15. @brauner is currently working on cephfs which theoretically could make it in 5.15 but may slip to 5.16. And then we need ZFS too which is a completely different beast and maintained outside of the kernel.
Once we have all of those in an Ubuntu kernel, we’ll be dropping shiftfs.