That clip and the attachment point appear to be corroded. Corrosion could certainly lead to a weakened attachment. I see that you are in Canada. Do they use salt on the roads there? If so, you might consider increasing the frequency of underbody washes.
clues
clip ear bent
probably the last remaining secure point before the event
lifted clip indicates it was ready to give up the ghost
it was a noble fight
overwhelmed by the forces of nature
what occurred
potentials too numerous to pin down
silver lining
chance to treat rusty points of contact
rust proof new spring clips