First reason I think of to use fde all the time even if it's automatically unlocked, is it's simple to securely delete everything all at once. Just delete all the keys or overwrite that section of the desk.
Yes, you can have docker scripts decrypt a drive/storage. You might also consider an encrypted home partition separate from the root partition, or user space encryption of your home directory.
I think when people want to remotely decrypt fde the usual advice is installing dropbear SSH to remotely enter the password. Sorry for not providing links but it should be easy to find.
Just showed up when I was posting from this client (Eternity). I saw it for like half a second before the picture appeared and didn't bother digging to figure it a purpose
I have not tried Matrix yet but I hear it's a good replacement, fashioned more to the likes of Discord but I think it has everything you're looking for
The fight was fought, and systemd won. If you're looking to learn theory then by all means look into the alternatives, but if you're wanting to use what's in most systems then go with systemd.
I would totally have one as a pet but they do not do well in captivity.