btrfs was merged in Linux in a very different state than bcachefs is now; bcachefs already has about ten years of development behind it, whereas btrfs "only" had two years of development behind it when it was merged. It would almost certainly not be merged today.

I'm not saying you should switch all your critical systems to bcachefs on the day it gets merged as you can never be sure about the absence of bugs (even the relatively simple ext4 had some data-eating bug a few years after introduction), but the path to "recommended filesystem" will be a lot shorter than btrfs.

At this point, I would already feel comfterable running bcachefs on my laptop – the only reason I don't is that I just can't be bothered running a custom kernel for it.