Why are we even talking about 8k video? It's something that almost noone needs and even fewer people have to edit. My guess is most people are still happy with editing their FHD videos. Something that works well on a five year old laptop.
8k also future-proofs the footage. In the future we'll be wanting more than 8k for this.
Hopefully that helps. In your original example, you cited someone editing FHD doing fine with a five year old laptop, and now we’ve talked about why larger formats are used, and why someone upgrading a laptop would look at a benchmark of an intensive process, even if they themself don’t plan to run that specific process.
there will be 8k tvs, sure, but lets be real - the step to 1080p was massive, the step to 4k already couldn't fit in those shoes.
the step to 1080p I'd say that, for some, could have been seen even as a downgrade. It was possible to use 1600x1200 back in the late 90s and early 2000s, with CRTs. The concept of "high definition" was already known by PC users (gamers and professionals, that is)
4k is a nice upgrade, and I'd say that many professionals already were using it with proper monitors
8k eeh, we'll get there
The step to 1080p wasn't from 1600x1200, it was from PAL/NTSC (640x400 or 720x576). It was the biggest step by far.
Same thing happened to audio players with "better than CD quality". They never caught on because there was no need.
65" 4K TVs start at 74 Watts (max is 271 Watts). 65" 8K TVs start at 182 Watts and go all the way to 408 Watts. For what? An improvement you won't notice unless you get off the sofa?