It's orphaned in Debian as well, but I'm not sure what significant advantages it has over btrfs, which is very stable these days.
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Also see https://www.phoronix.com/news/Josef-Bacik-Leaves-Meta
Single, dup, raid0, raid1, raid10 have been usable and stable for a decade or more.
All the anecdotes I see tend to be “my drive didn’t mount, and I tried nothing before giving up because everyone knows BTRFS sux lol”. My professional experience meanwhile is that I’ve never once been able to not (very easily!) recover a BTRFS drive someone else has given up for dead… just by running its standard recovery tools.