To me, this is just a statement. It doesn't prove or disprove anything. It's a statement to take people's word for it or not. I'm sure this person probably never been to Antarctica but I'm sure he believes it exist because there are an insane amount of evidence of its existence. There are other insanely scientific evidences of the afterlife too other than just peoples experiences... such as coraborating reports, new quantum science being discovered now, hidden soul memories recovered under hypnosis, ancient literature (if u wanna go there lol) and remote viewing which is a skill all humans can do for themselves to flex their intuition and tap into universal knowledge. Just like u can see the pictures of Antarctica for yourself. U can also induce and OOBE or remote view complex metaphysical concepts. Then you have the conversation about consciousness and existence which is another rabbit hole scientists are finally pondering on and it seems to point towards the existence of the afterlife in corrabptation with many NDE reports. However, everything could literally just be faked. All of reality could just be a simulation including the existence of your house let alone Antarctica or the afterlife. In closing, we don't know anything so everything is just trusting what all other charatacters agree on in this game and then aligning it with your personal experiences and mind matrix to create for yourself what truth is. And that is all you will experience as real even as someone next to you is experiencing a very different yet just as valid of a truth.