How to avoid horizontal scrolling in "systemctl status"?
You could use the --no-pager option in conjunction with the --full option, which will force the lines to wrap:
systemctl status --no-pager --full
If you want to preserve the paging functionality, you can just pipe the output of systemctl status to less / more directly, since connecting the command's STDOUT to a pipe will force the command to print a raw output:
systemctl status | less