However, the line length Wikipedia picked seems to be a bad compromise. At around 120 characters per line it‘s double the recommend line length (60 characters).
If you look at newspapers, magazines and books you will see the 60 character rule of thumb adhered to pretty exactly and thoroughly. It‘s just a typographical best practice.
On the web and on wider maximized screens the issue is always the white space. Newspapers solve this issue with columns. However, that‘s not a realistic solution on the web (not so much for technical reasons, mostly because scrolling is fundamentally incompatible with columns).