Funnily enough (not funny actually, considering the war crimes and all), the Old Testament says that the Jews/Isrealites will never get rid of other people living in the area due to not driving them out in their original conquest.

Interesting, I've not heard of this shell of ice, and I believe in a young earth. I have heard though of a similar hypothesis based in Genesis 2:5-6 which proposes that it did not rain before Noah's flood and that plants were kept watered by a heavy mist and/or extremely humid atmosphere. Acoording to this idea, that excess water in the air and ground would've been all condensed by God as part of the flood.

I'm not sure I entirely agree with the hypothesis, and I do not believe it is essential biblical knowledge so I don't concern myself with it, but I have heard it before.

I agree with others, this seems like a flat-earther belief that has gotten mixed with Christianity's creation story.

I've heard of it before while browsing the internet, but not from any Christians I personally know. All the Christians I interact with (myself included) believe in a literal interpretation of the creation but nobe of us believe in a physical firmament. I will note that a single man I know denies the moon landing (for reasons I haven't bothered to ask) but even he still believes in a spherical earth and heliocentric orbit.

My understanding of Genesis 1:6-8 is that the firmament mentioned is the earth's sky or atmosphere itself, and not a physical barrier at the edge of the atmosphere. The easiest way to show this would be Genesis 1:20 where birds are described as "flying in the firmament of heaven". If the firmament was a solid object, birds could not fly in it.

I don't think there is a cutoff.

My 80yo grandfather still pulls out the gamecube to play Mario Kart (and for a long time noone else could beat him). My grandmother before she passed was not really big on video games but would play one specific level of crash bandicoot over and over again.

My 45~yo mother streams minecraft in her free time and is even looking to start up a YouTube channel with more content. Some of her viewers are close to her age and when she was playing more Counter Strike than Minecraft the server she played on had adults of all ages on it.

I'm getting closer to 30 every year and I can't see myself ever quitting games. If/when I marry I imagine playing games will just be part of family bonding. I may get worse as I age like my grandfather but I doubt I'll ever stop.