Formatting with Pango Markup has been shown to work on one --info --text entry in this stackoverflow answer.
I would like to use a monospace font for a multiline list of block devices (avoiding multiple columns):
IFS=$'\n'
zenity --height=480 --width=700 --list --hide-header --column=device --text="Select a partition:" $(lsblk -n -o NAME,RM,TYPE,TRAN,FSTYPE,LABEL,VENDOR,MODEL)