I think the problem with btrfs is that it entered the spotlight way to early. With Wayland there was time to work on a lot of the kinks before everyone started seriously switching.
On btrfs a bunch of people switched blindly and then lost data. This caused many to have a bad impression of btrfs. These days it is significantly better but because there was so much fear there is less attention paid to it and it is less widely used.
@drspod @possiblylinux127 Since I am using Intel graphics and there is an Xorg X server baked into the Linux kernel for Intel graphics, I switched to it at that time and have been using it ever since.