Competitive debating largely ignores the meta-debate of what motion should be debated. In 2016, the UK electorate was asked whether or not we wished to leave or remain in the EU. Prime Minister David Cameron argued that the only sensible answer was Remain, but simply asking the question implied that either answer was reasonable.
Or consider climate change. We could debate the motion “This house believes veganism is necessary to meet the threat of climate change”, or “This house believes a carbon tax is sufficient to meet the threat of climate change”, or “This house believes there is no threat from climate change”. Which motion gets attention may be more important than any debate that follows.
Debating also feeds some of our less admirable urges. It sometimes pretends to be a search for the truth, but the real goal is not truth but victory.