i highly doubt that bitcoin halving will ever be canceled because of a lot of reasons that would cause the delay or the complete cancel of the halving
first of all people would be really sad that their bitcoin price will not grow at all besides that investors would quit from bitcoin so the price would be dumped alot
yes,we all will upset if bitcoin halving canceled,and its not gonna canceled for any reason,but its too much if investor would quit because halving is canceled,even bitcoin halving canceeled,they will stay on bitcoin i think.