The Internet and web applications have been enablers for these server farms, for these mainracks, if you will. People use these web apps on smartphones, on notebooks, on tablets, and on the fading desktop. The client paints pixels while the server farm — the mainrack — does the backend work. More than a dozen iterations of Moore’s Law later, and the Wheel of Reincarnation has returned us to terminals connected to Big Iron.
And there’s the rub. The movement to replace the mainframe has re-invented not only the mainframe, but also the reason why people wanted to get rid of mainframes in the first place.