Why do many graduate programs in mathematics (United States) still have foreign language requirements today (in 2010s)? As far as I know, nowadays most of the mathematical literature is written and published in English and mathematicians communicate with each other in English. Although there are certain number of books written in other languages (like EGA), but at the same time their counterparts also appear in English (like Stacks Project). However, many graduate programs still require their students to pass a language translation test in French, German or Russian (which a paper dictionary, not a dictionary app in cellphones, which seems even more ridiculous to me...). I wonder what makes it still necessary to have foreign language requirement as of 2010s.

I believe my question has different focus than this one 

Mathematics Ph.D program foreign language requirement

Where the questioner specifically asked for advice for the most useful language among French, German and Russian:

I personally have no preference on which to learn, but I was wondering if there were other reasons that would make one language more advantageous over the others in terms of a general mathematical career.

while I am asking why we ever need a second language for mathematical study in 2010s:
Just an anecdotal answer: My mathematics PhD program (at UC Berkeley) had a requirement to pass a language exam. This involved translating to English 1-2 pages excerpted from a mathematics paper written in French, German, or Russian (student's choice). We were given several hours to do this, and the use of a paper dictionary. 

I did not, and still do not, speak a word of any of these three languages (unfortunately). But I took the exam in French and passed easily thanks to the high number of cognates between mathematical French and English, context clues (being somewhat familiar with the subfield of math helps), and the fact that I had plenty of time to look up any words I didn't know in the dictionary. 

The main thing I gained from this experience was confidence that with a little extra effort, I could actually read math written in French. Since then, I have at times had reason to use this skill that I didn't know I had. 

I believe Berkeley math did away with its language exam requirement the year I graduated (2016), and I think this was an entirely sensible thing to do. But I would encourage all grad students to get some experience reading papers written in a language they don't speak!