Debates usually don't serve any purpose! Debates between unequal people on unequal grounds are completely useless.

Krishna: I haven’t watched it. But still I want to say a few things because I participated in such debates too earlier.

"Debates don’t show who is right. They only show who is best at debating. Only evidence can show who is right, not debates. But what if the other person debating doesn't accept your genuine evidence? What if people watching don't know what scientific evidence is? What if they think the evidence shown is just an opinion of the debater?”

This is what we face most of the time during debates and therefore, I usually don’t like to debate on ordinary platforms.

Bill Nye is not a scientist but it seems debates science topics well. I never watched him debate anything so I can’t tell you for sure.

Many scientists are uneasy about the debate regarding Evolution Vs. Creation theory. The reasons for this argument are six (1*):

1. Creationists specialize in the what’s called the Gish gallop — a rapid-fire listing of supposed weaknesses of evolution that, in a limited-time format of a debate, cannot all be properly answered.This leaves the audience with the incorrect impression that evolution is shaky science.

2. The debate “Is Creation a Viable Model of Origins?” is itself problematic. Because evolution is all around us, all the time. Evolution is why we need to get a new flu shot every year. By putting a scientist and a non-scientist on the same stage together, there is a real danger of legitimizing creationism and giving the appearance that both sides are equally valid. Anyone is free to hold whatever beliefs or opinions they like, no matter how unscientific or false. But there is no obligation to portray both sides as having equally strong or valid scientific arguments, when by any measure they do not.

3. Another problem is that because Scientists and creationists are operating on different sets of assumptions, there will be no meeting of the minds. For a true, fruitful debate, the participants should speak each other’s language and accept definitions that provide common ground for a discussion. True discussion is difficult here because they don’t even accept the definitions of the words the other person uses.

Scientists and creationists are unlikely to find common ground.
For creationists the Bible is their ultimate authority. They are starting with the answer — that the Christian God created the universe as described in the Book of Genesis — and trying to make the facts fit that interpretation or conclusion.

The problem is that that’s not how science works. The purpose of science is to gather facts in a systematic way and follow the evidence to its logical conclusion, not prove a certain premise.

4. Religions are based, by definition, upon faith instead of evidence, and that’s why debates about religion are often fruitless. A few good points — or, depending on the tone, zingers — may be made, but it’s unlikely to change many minds. Those who walk in convinced that evolution is true (or a hoax) will likely leave the same way.

5. Appeals to emotion and faith often win the day regardless of what the scientific evidence says. That is one reason why, for example, anti-vaccine propaganda is persuasive to many people. One of the most compelling “arguments” are vivid, personal stories highlighted by anti-vaccination activists like Jenny McCarthy. It’s a classic case of science versus anecdote.

Statistics and authoritative, impersonal medical information will never be as compelling as an emotional, tearful story told by a mother holding the daughter whose autism she blames on the vaccine. All the facts, data and research fades away under the glare of human emotion and faith. The people who do best in these debates are those who establish rapport with the audience, and who come across as trustworthy and believable. Affect is all; content is secondary. Which is another reason why formal debate is not the way to educate people about evolution or science in general.

6. Changing minds is unlikely in such a scenario.

"Science adjusts its views based on what’s observed. Faith is the denial of observation so that belief can be preserved." - Tim Minchin

This is my experience too while dealing with people of religion and art! I have learned the lesson: never underestimate confirmation bias.

Debates don’t change anyone’s mind most of the time.

But presenting data and facts don't win arguments! Why?

A group of Dartmouth researchers have studied (1*) the problem of the so-called "backfire effect," which is defined as the effect in which "corrections actually increase misperceptions among the group in question." According to them... people typically receive corrective information within “objective” news reports pitting two sides of an argument against each other, which is significantly more ambiguous than receiving a correct answer from an omniscient source. In such cases, citizens are likely to resist or reject arguments and evidence contradicting their opinions – a view that is consistent with a wide array of research.

So when people read a news story that presents both sides of an issue, they simply pick the side they happen to agree with and it reinforces their viewpoint. But what of those individuals who don't simply resist challenges to their views, but who actually come to hold their original opinion even more strongly?

The authors describe the "backfire effect" as a possible result of

the process by which people counterargue preference-incongruent information and bolster their preexisting views. If people counterargue unwelcome information vigorously enough, they may end up with 'more attitudinally congruent information in mind than before the debate,' which in turn leads them to report opinions that are more extreme than they otherwise would have had."

Also cognitive dissonance, or the uncomfortable tension that comes from holding two conflicting thoughts simultaneously plays a role and makes people reject things that don't make them comfortable processing them. Then people spin-doctor facts to fit preconceived beliefs to reduce dissonance.

Why Facts Won't Help You Win Arguments

And journalists and anchors give equal importance to both religion based opinions/beliefs and evidence based on data while conducting debates. Like Aristotle said, "The worst form of inequality is to try to make unequal things equal!"

More often than not, there is no “opposition party” or “other side” in science. There can be disagreement between various scientists when sometimes the research is incomplete and inconclusive. This can be reported or debated. But non-experts cannot be given 'opposition status' in science. Someone who objects to scientific facts on non-scientific grounds simply cannot form part of the debate. There is the data and what it means. And there are facts whether anybody agrees with them or not. You got to report/say only them. Period (2*).

“One cannot really argue with a mathematical theorem.” - Stephen Hawking

I think these debates between unequal people on unequal grounds are completely useless. They don’t serve any purpose at all.

Footnotes:

1*. Why it is difficult for scientists to debate controversial issues w...

2*. Why science journalism is different from other forms of journalism