The Brtfs commands are very poor compared with what ZFS offers. The ZFS commands are organised around the end user: the system administrator. The Brtfs commands are not.

As an example, you're running low on space and need to find out which datasets (subvolumes) are using the most space. How do you do that? With ZFS it's a single command which runs in a few milliseconds. With Btrfs...

Hey everyone has a different taste, but vdevs, datasets, and pool are for me much more logical than lv's and lg's (pun was NOT intended).