here are is my setup:
castej@castej-desktop:~$ sudo ls -l /var/lib/docker
total 60
drwx--x--x 4 root root 4096 Jul 7 14:54 buildkit
drwx--x--- 2 root root 4096 Jul 7 20:31 containers
-rw------- 1 root root 36 Jul 7 14:54 engine-id
drwx------ 3 root root 4096 Jul 7 14:54 image
drwxr-x--- 3 root root 4096 Jul 7 14:54 network
drwx--x--- 79 root root 20480 Jul 17 21:33 overlay2
drwx------ 4 root root 4096 Jul 7 14:54 plugins
drwx------ 2 root root 4096 Jul 17 21:01 runtimes
drwx------ 2 root root 4096 Jul 7 14:54 swarm
drwx------ 2 root root 4096 Jul 17 21:33 tmp
drwx-----x 2 root root 4096 Jul 17 21:01 volumes
castej@castej-desktop:~$ sudo du -chs /var/lib/docker/
24G /var/lib/docker/
24G total
castej@castej-desktop:~$ docker info | grep -e "Runtime" -e "Root"
Runtimes: io.containerd.runc.v2 nvidia runc
Default Runtime: nvidia
Docker Root Dir: /var/lib/docker