Getting a CPU Z validation is a sport, nothing more. But they have to develop tricks and techniques to further their sport, which may have other benefits in terms of understanding the hardware.

What is preventing someone from doing the same with the latest Intel chip? Do they fry immediately or do they just emergently shut down?

Different chips have different limits. I used to do some of this competitively back in the day. Different architectures can't get as high max frequencies, some respond differently under the extreme cold. These records are typically done using liquid nitrogen or phase change cooling and a lot of chips will freeze up below a certain temperature. Then its also a toss up between different individual cpus of the same model. It's a bit of a crapshoot.

Hell I even remember back in the day hunting down RAM produced from specific batches

Intel chips overclock even higher[1], but this article is about the AMD chips just released this week.

[1] https://www.extremetech.com/computing/250622-intel-core-i7-7...

I would guess that the remarkable fact is exactly that this CPU is still able to work somewhat properly at these extremely out of spec conditions, thus proving a good design/production process/idk

Yeah, beside the "why not" factor, it's always reassuring that your device has so much room left.

AFAIK, other than "because we can", "stable enough to get into an OS, but not to be reliably used" is pretty close to "stable", so assuming tech iteration doesn't result in a quality drop, you can think of it as a "Coming Soon" for what a generation or two later's high-end chips can be pushed to.

I am not sure if they got into the OS at that speed. From the video I got the impression that they adjusted the core frequency and voltages using software, once inside the OS.