My screen - like probably a significant portion of screens out there - is wide, 16:10 or 16:9. So without multi-column layout, I have three layout possibilities: Long lines (hard to read), large font (wasting screen real estate) or some form of fixed-width central column with auto margin (also wasting real estate).

With multi-column text layout I (think I) read faster. It is much easier for me to remember where on the screen a certain passage was in case I have the desire to re-read at a later point in the text (say, because I am not sure if I understood correctly). Plus, for long texts it is much easier to jump to an earlier part of the text when it is still visible than to scroll back.

So I wouldn't flat-out refuse that Good may come of this. I don't see the application of multi-column text on a phone screen given its size but tablets seem to have reached sufficient size and resolution. Multi-column text still breaks the way I usually read on the web, but I feel it might be worth getting used to.