Another example from another sport.Billy Casper defeated Arnold Palmer in US Open championship 1966.Arnold was leading by 7 strokes with nine holes left.Casper got to tie Arnold and won the playoff the next day.Arnold never won another Major.Incidentally I went to the Olympic Club that year to watch Ben Hogan play.
Highly tenuous link, golfers and horses.
Palmer was already on the decline by then and in his late 30’s, he hadn’t won a major since 64 and despite "having his heart broke" by Casper still managed plenty of tournament wins after and a couple of seconds in majors. It just affected him actually winning a major did it?
Greg Norman bottled more majors than anyone and must have had his "heart broke" several times but still managed 2 majors.
Even so it’s hard to imagine how a commentator could deduce a horse having their "heart broken" during an actual race commentary.