DKIM protects both the sender and receiver by authenticating an email address to ensure that it is safe. Exploiters tend to use emails to send out spam without the user knowing. Once the issue has been detected, it may be too late as the email addres will be blacklisted and efforts to resolve this becomes more time consuming. Therefore, it is best to be proactive rather than reactive.
DKIM also prevents your emails from being marked as spam, which tends to land in the receiver's junk folder. Ensure that your emails are well protected by removing suspicious emails in your inbox.