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".

Then you look further and see that it’s done with coffee machines, motors (of all sorts), and just about any other device you can find, make or name.

Wanting a fast/strong/powerful/quick X is a fairly common thing for many of us.