Our assessments of the question of whether to be a believer of one kind or not cannot be, and I think should not be, affected completely by arguments and evidence. And if we do change our minds about something because of the evidence, it is usually a process that percolates over a period of time. Most of the time, we don't hear an argument that we decide is a good one and think "I never thought of that! I must be completely wrong!" That isn't how we operate.
Where religious conversion, or, I suppose, deconversion is concerned, there is a dimension of it that is open to rational debate, and a part that isn't really debatable. One must find the reason to make the move one is considering, but then one must have the will to take that step and accept a different position that may change your life forever.
Nevertheless, when we are in discussion, we do the most for our respective positions by sticking to the issues and debating them as forcefully and as charitably as we can. That's what we're here for. Let the conversions and deconversions fall where they may.
There is nothing I enjoy more than a discussion with an atheist in which I succeed in making Christianity just seem just a little more reasonable to him than when we started. I remember conversations I had 25 years ago with a fellow grad student at Illinois who liked to argue down Christians. I heard later he said after arguing with me "Boy, this is tough! I'm used to Christians just folding, or appealing to faith." Now, he remained a firmly committed atheist, and so far as I know, he still is. But who knows?
The internet is a little bit driving, in that we deal with people but we don't actually see their faces. Hence, I think, we are more likely to call each other names and flip one another off (or the cyber equivalent thereof), because we do not know one another as persons.
I will say this: ridicule and abuse are, at least for me, very bad PR. I've heard enough anti-Christian ridicule to last three lifetimes. I happen to think that the culture of unbelief in many secular philosophy departments is sustained not by argument, but by intellectual peer pressure. I think about the people I have found impressive in my intellectual life: C. S. Lewis, Ted Guleserian, Doug Arner, Bob Prokop, Joe Sheffer, Don Saliers, Hugh Chandler, Patrick Maher, Bill Hasker, and there are others. Most are Christians, others are not, but I think their character, as well as their intellectual capacities, made a difference to me.
Honestly, in dealing with some internet atheists, I think to myself "You know, even if ____ had some good arguments, if that's what atheism does to you, I never want to be like that. And I am sure that many skeptics react the same way in dealing with some Christians.
I am sure if I had been Lewis's friend Christian friend Arthur Greeves, I would have thought that I had lost all the arguments with my young atheist friend. So I am going to dedicate this post to all the Christians who got into arguments with the young C. S. Lewis and ended up thinking they had lost.