I'm not at all sure that that was the point of the article, and if I felt like being trite I could list a slew of reasons for debate to exist that are mostly independent of how closely the activity mirrors actual or ideal political discourse.
But, for what it's worth, high school debate programs are more properly speech and debate programs. Tournaments do include indirectly-competitive events such as oratory, in which competitors give a ten-minute freeform speech and the rhetorical qualities you seem to value are encouraged and rewarded. Debate is just one aspect of the activity.
Being able to impress "flow judges" has zero bearing at being able to persuade anyone else. Which it would seem would be the one useful thing you would want to come out of a debating community.
If we need a new format, I suggest an "Obama" debate style. The man clearly understood the policies and their implications, but spoke in a way that moved people deeply at an emotional level, and came away inspired instead of pissed off at their enemies. God, that seems like such a long, long time ago.