Facebook runs servers a lot different than a home oriented distro is likely to be run. I was there through aquisition from late 2014 to late 2019, and I mostly avoided production operations in FB land.
I don't remember hearing about any power failures --- either UPS and transfer switches all worked 100%, node replacement covered any issues 100%, or I just wasn't in the loop. This isn't common at home; most people have at least a few brief power blips every once in a while, and those with many often get a UPS, but home grade UPSes often fail. I'd expect at least one unexpected power failure per 3 years in a home environment.
Most of FB production is built from ephemeral containers. If a container host crashes and restarts and the filesystem is corrupt, the container would be rescheduled somewhere else, and the host would be sent for repair (reimaging) automagically, and a product team like mine would not really know unless they really looked, maybe just that the container moved. That's not realistic for home users.
The containers themselves were short lived for many reasons. I'd estimate most of them lived for less than a month. A home user distro install often lasts much longer.
That said, I don't remember seeing disk corruption, but I do remember a series of issues where we couldn't write to disk because it was full, with disk usage of maybe 60%. As I recall, there was only one couple week period where that happened. This was resolved in the moment by replacing affected containers with new ones on other hosts, and permanently by a fix in the host kernels; broken filesystems were not fixed, they were abandoned. This isn't great for home users either.
There was a separate class of operations for persistent data storage; although there was work to containerize that as well, I had little visibility. Persistent storage machines were different and I don't know if they used btrfs or not.
This all doesn't mean it's not a good filesystem for home users, just that Facebook's endorsement doesn't transfer as the use case is much different.