It was the prots celebrating Reformation Sunday in a Catholic cathedral that not only was an annoyance, but a heretical act from a Catholic perspective.
From another article I found this statement, "The Catholic Cathedral of St Michael and St Gudula hosted the service with the United Protestant Church in Belgium, the country’s largest Protestant denomination."
So the "prots" had permission to use the Catholic cathedral and you support jerks who interrupted their service. The heckler's veto should never be celebrated. Anyone who thinks the heckler is noble is also a jerk. Anyone who portrays the heckler as the victim is an ever worse jerk.
“a heretical act from a Catholic perspective”
The “Catholic perspective” is whatever their church hierarchy says it is. If they are okay with it, then wouldn’t it be YOU who was the heretic for dissenting?