Encrypts root despite config not specifying encryption

[jakubgs]

I tried installing Ubuntu by encryptin a dedicated /data volume like so:

DRIVE1 /dev/nvme0n1
DRIVE2 /dev/nvme1n1
SWRAID 1
SWRAIDLEVEL 1
HOSTNAME Ubuntu-2004-focal-64-minimal
CRYPTPASSWORD <SECRET_PASSWORD>
PART swap swap 32G
PART /boot ext3 1024M
PART / ext4 50G
PART /data ext4 all crypt
IMAGE /root/.oldroot/nfs/install/../images/Ubuntu-2004-focal-64-minimal.tar.gz
Ubuntu-2004-focal-64-minimal-hwe.tar.gz

But when I mount the volume it looks like the installimage script encrypted both / and /data:

root@rescue ~ # mount /dev/dm-0 /mnt
root@rescue ~ # cat /mnt/etc/fstab 
proc /proc proc defaults 0 0
# /dev/md/0
UUID=388b8803-559a-4997-b980-5d95b8f9a0a6 none swap sw 0 0
# /dev/md/1
UUID=5f925bfa-1822-4a95-988f-52c0596d3a58 /boot ext3 defaults 0 0
/dev/mapper/luks-eb7cde07-90e6-4487-bca2-c6002e0cb9fc / ext4 defaults 0 0 # crypted
/dev/mapper/luks-b4f37da6-54bf-4a03-bb45-8a292af702b0 /data ext4 defaults 0 0 # crypted

Which is obviously wrong.