No, that’s pretty straightforward.
Do a pg_dump to backup your database, copy the /opt/indico/archive folder and possibly your /opt/indico/etc/indico.conf and /opt/indico/logs/ (if you want to keep that) as well.
Then on the new system you follow the installation guide but after creating the database you pg_restore it and DO NOT run indico db prepare (nor indico setup wizard, unless you want to regenerate your indico.conf which is probably faster than copying it if you didn’t customize anything in there).