In my case I need to use a named volume for docker swarm, also I can reuse a named volume in other services.
If your not using swarm then just a bind mount should be fine
Yes, but no. There is still a lot of places using old fashioned VMs, my company is still building VMs from an AWS ami and running ansible to install all the stuff we need. Some places will move to containers and that's great, but containers won't solve every problem
If your router is setup to only allow in the ports with a service hanging off it, like SSH. Then a firewall wont add anything your router doesnt.
On the flip side, if your running any kind of VPS or directly accessible server, like a VPS or dedicated server. Then a firewall is required.
Now protecting your server from other things on your local network might something you want to do, think IoT stuff getting popped and being used to hack other things on the network
The morale of the store is, read the release notes to see what's changing.
I don't blinly update everything, but I do try to be on the more up to date end of things.
Case in point is nextcloud, that's now on 31.0.0. I don't ever jump to the latest untill the first point release is out, as nextcloud 31.0.1 is now out Wednesday night is nextcloud update time
Depending on what your server is doing, swap use is normal. But if it's into swap cuz ram is full, you will find it grinds to a halt.
Use
free -mh
to see what the memory use is, there is a way to reduce the swapiness if your running a database server and is advised.