T'were me, it would be repaired and repainted; but I'm not fond of the colors or scheme anyway. I think that if you wanted to keep it going, a piece of aluminum or CF tubing, epoxied to the cleaned-up (rat-tail file used with masking tape) remains of the braze-on would serve well enough, the lateral stresses of the cable notwithstanding.

I was going to suggest adding a "panel" to the top tube (covering braze repair), but the braze-on is a bit too forward for that. Perhaps a short band at the b-o, with pinstriping and a suitable decal on each side to give the anomaly some graphic logic?