Well he cheated a bit as there is now a really big unit and a smaller one.
His idea to use an external power supply is interesting. I have a problem with my PS4 Pro power supply that makes a clicking noise since I tweaked the cooling system. Now the cooler runs slower but the power supply no longer gets enough air-flow and the clicking noise starts after a while. If you run something system-heavy so the cooler spins faster, the clicking goes away as there is than enough air-flow.
That might get solved with a external power-supply.
Edit:
oh wait, the PS4 Pro power supply has an extra cable and not only the 2 pins ... I guess I have to somehow increase air-pressure in my console to reduce the clicking noise ...

buying a PS5 can be cheaper ^^ if it would be available. But I won't buy one in that big form factor. It is just to big for my taste.