XFS has long been working toward online repair functionality and it began landing last year and over the past several kernels has seen more functionality implemented . With Linux 6.9, there's yet more online repair work.
XFS with Linux 6.9 allows online repair handling more on-disk structures for repair, reporting corruption of metadata to the health tracking subsystem, reduced memory usage in some situations, and a variety of other enhancements to the online repair functionality as well as numerous code cleanups.
Among the on-disk structures now working for online repair are the inode's mode field, quota counters, link counts of inodes, file-system summary counters, and support for in-memory b-trees.
Outside of the XFS online repair work, there are various bug fixes and other code improvements as outlined in this Git merge for v6.9.