The last paragraph nails it:

"Between the two, Times New Roman may be the lesser evil: it is more widely recognized, and it doesn’t clash with the official context as overtly as Calibri does. Still, [...] [t]here was no need to dress up a political gesture with faux-erudite claims or to lavish praise on a mediocre typeface."

Times may not be great, but the choice of Calibri was one step away from Comic Sans.