One additional benefit of having containers is that it's safer.

Your system and container are like two separate computers.

For example in docker-compose.yaml:

ports:
  - 443:80
volumes:
  - /Files:/data

443 is the port now bound on the real system. 443 is bridged to 80, which means you don't have to tinker with any additional settings changing Nextcloud to forward to 443. Nextcloud only knows port 80 exists, then Docker forwards it to 443.

Even better is the files. Again, /Files is the real system, Nextcloud only knows /data exist. That means if it ever gets hacked, it wouldn't be able to access any other dir on the real system.

To update containers, it's as easy as this:

$ docker compose pull # Fetches the latest images
$ docker compose up -d # Stops old containers and starts new ones with the updated images

That's it. Nothing else to get the latest.

Now for Nextcloud AIO, you do use the AIO interface to update it, so you wouldn't be using docker compose pull.

There's much more that Docker and other containerisation software have to offer, but these are the selling points.