Running ZFS since it was originally released on Solaris (June 2006) with zero problems (then FreeBSD, then Linux), including on RAID-5/6 (RAID-Z1/2) configurations, which btrfs still does not recommend using all these years later:
* https://btrfs.readthedocs.io/en/latest/btrfs-man5.html#raid5...
What have the btrfs developer(s) been doing for the last decade(+) that the code is still of debatable dependability?
From what I understand single copy setups, RAID 1, and RAID 10 never had the same problem. It's left a bad taste for a lot of people though.
Very early ext4 versions also had some data loss or data corruption, but I never hear people dismiss it completely for that brief spot of its history. Maybe part of that is because it was around 17 years ago and it's been a reliable default OS for many years now.