One can be completely, 100% certain of very little.
But I don't believe that when you drop a light bulb on the ground, that there's some light bulb heaven where that bulb goes to shine again. No one does.
And our brains are also complicated machines - or at least, we have done experiments on whether this is so for hundreds of years, and every single verified experiment says that same.
I'd love to believe that my consciousness continues after my body is gone, but where would it be? There's absolutely no hard evidence that this happens.
More, billions of people believe that our consciousness does survive... but then they disagree on absolutely all the other details about the universe, which is pretty telling if you ask me.
So I'm not 100%, completely sure but I'm not going to believe ridiculous, irrational things where all the concrete evidence is against it, simply because it makes me feel better.
Comparing this belief to the belief of Christians is logically unjustified and kind of insulting.
Christians believe in this elaborate fantasy world for which there is no evidence at all, and indeed, we are supposed to believe precisely because it's so irrational. That's a big stretch.
But the writer of this article simply believes that the world is as it appears to be: that things are as they seem. That's not a stretch at all. It should be the default belief system, and the only resaon it isn't is because people hate the idea of personal extinction - I know I do! - and find it impossible to comprehend.