I don’t think that explanation makes sense. It isn’t about regular computing power, it is about the hash rate of the mining hardware. They use specialized hardware (ASICs), and if you look on this page you can see a breakdown of the hashrates:

https://en.bitcoin.it/wiki/Mining_hardware_comparison

The top one (other than the Dragonmint miners which are not listed) is the Antminer S9 which you can see was released over two years ago.

If you are aware of some new mining hardware that is much faster please let me know.