Are you sure you haven't visited hacker news by mistake?
Hardware overclocking requires a decent amount of knowledge, most of it obtainable only through months of trial and error, and a lot of tuning to push dozens of often conflicting parameters just right. Extreme overclocking requires that much more. If what they're doing is simply "pushing a button", then programming and system administration can be reduced to that too, along with many other things.
You simply can't get full performance from modern systems without some amount of overclocking, and things like PBO and XMP/EXPO profiles are far from what your hardware can achieve because they have to be very conservative, or many systems won't run without additional manual tuning, which most consumers won't do.
(Except for closed systems like Apple's where your hardware doesn't belong to you and you can't change anything anyway.)
So one immediate thing overclockers provide are general guidance on what you can expect to achieve and what thing to tune which way to get close to maximum performance from your hardware without spending months on it like they did. I heavily rely on such information. My system would be at least 25% slower if not for these "button pushers".
I wouldn't trust an overclocked system as a server or to compile. Especially not long term w degradation. Can't use it for CAD bc it'll mess up the PCIe timings I think. Looks like a giant waste of time and money to me, but sure to each their own. I bet it's difficult, but seems also pointless. If they were really knowledgeable they'd get out an FPGA and go design their own SoC instead of filing down intel's for a speed bump. Just not relevant today
Again bringing it back to the drag racing analogy… you wouldn’t commute to work in a drag racer. Thats not the point. The point is to push the hardware to the point of absurdity, just like drag racing.
If extreme overlocking isn’t for you then that’s fine.
PCIe issues are only really a thing with BCLK overclocking on systems that lack a secondary external clock generator. BCLK overclocking is a pretty uncommon practice that isn’t practical for day to day usage.
The bigger issue is that helium is a functionally finite resource, and does not remain in the atmosphere (at least IIRC it literally just floats up until it gets blown into space).
The bigger local issue you run into with liquid helium and liquid nitrogen is having it evaporate in an enclosed space. You can "easily" create an environment leading to inert gas suffocation (a real hazard in some industrial cases) - in reality any simple case like this is unlikely to be using enough of N or He, and is unlikely to be sufficiently enclosed, but in principle it would be possible - maybe if you were in a basement and spilled an inexplicably large thermos of them it could do it.