> Death is the end of everything for you.
Both of you these are objective. You can think you are insignificant or you can think that you are part of the big bang which is still happening. It's just narration and if it makes no practical difference (as it would seem in these cases), everybody can choose whatever makes him feel better, there is no need to put down the other narration.
And you can only choose what makes you feel better in matters that don't matter. In all others you are almost always better off choosing what is actually correct.
You can choose a narrative that pi equals 3 because it makes you feel better but you won't be doing world or yourself any favors if you choose to make real world decisions based on that narrative.
If you want analogy - we are looking on the river and we see a vortex, then it disappears. Parent comment is like - oh, the water is again flowing in the straight flow. And your version is - there was a vortex, and now it's gone forever, nothing left of it.
So there is "you" as there is a "vortex". It's not just a language construct. It's a language construct that describes impactful but sadly transient phenomenon.
Except it doesn't. Death is the end of everything for you. It's ultimate loss of any game you might have participated in. And there's nothing else. When you die then there's no longer any you. And there will never be you in any shape or form. When you die it's as if your family home burnt to ashes along with your family inside and family business and there not even any cinder left. What was there doesn't exist anymore.
Once you actually understand death without the layer of culture that we built to distract ourselves from the reality there's really no wonder why some people would take any chances to avoid it in any way conceivable.