If you are using data=journal, as I was, the move to ordered requires that you have a battery backup that communicates with the system(s) it backs up.

Apc makes them and the apc kernel module works with them and is very well documented.

Two years to purchase and implement power failover and shutdown is plenty of time.

No, the journal is not deprecated. Only data journaling is.

Metadata is still journaled and is what most people have been using all this time.

Okay, but no mention of alternative modes of operation for "those very concerned about data integrity and safety"?

What reason is there to use EXT4 if not for the journal?

Just use F2FS or BTRFS at that point. (or ZFS if you're fine with out-of-tree)

That’s too bad. It was great for use as a root fs on VMware when you had an unreliable NFS storage. Kept every VM from needing an FSCK on recovery.

But why they need to remove it? Maybe just left it as a non-recommended option or just create an alternative. A great amount of people, like me for example, have a volatile enviroment that makes this a need.

Although I do prefer Btrfs for that task, I understand why some people need it in Ext4.

Wasn't the journal the main selling point in the transition from EXT2 to EXT3? This seems kinda backwards, what even is the rational?