Cron/Anacron vs. Systemd

In favor of Cron

• A simple one line entry /etc/crontab and your job is set to run

In favor of systemd

• Consistent run time environment with the same environment variable set. This solves a common problem with Cron jobs: They run fine in one environment and not via cron because different PATH or other values in the environment.
• Better logging! systemd captures STDOUT and STDERR of your job and stores it in the systemd journal.
• Better job status. You can use systemctl status your-service to check the status of what you ran. Outside of combing logs, cron offers no structured way to query the service status.
• Better timer status. Use systemctl list-timers to get a summary of enabled timers and see when they last ran and when they will next run.

In summary

Systemd timers have some overhead to learn and setup, but provide a number of benefits. There some packages like systemd-cron and systemd-cron-next that allow you to have cron entries converted to systemd-timers, to try to provide a best-of-both-worlds solution