> The more plausible explanation is that they want to copy the learned people at the medieval time, i.e. Arabic speaking people, during the European dark ages by imitating the Arabic styled robe with the robe and the turban.
The academic dress found in most universities in the Commonwealth of Nations and the United States is derived from that of the universities of Oxford and Cambridge, which was a development of academic and clerical dress common throughout the medieval universities of Europe.[1]
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The modern gown is derived from the roba worn under the cappa clausa, a garment resembling a long black cape. In early medieval times, all students at the universities were in at least minor orders, and were required to wear the cappa or other clerical dress, and restricted to clothes of black or other dark colour. The gowns most commonly worn, that of the clerical type gowns of bachelor's degrees (BA and BS) and master's degrees (MA and MS), are substantially the same throughout the English-speaking world. All are traditionally made of black cloth, (although occasionally the gown is dyed in one of the university's colours) and the material at the back of the gown is gathered into a yoke.[2]
Medieval Arabic-styled robes were not necessarily black, but also white and many dyed colors. They were shaped differently and had a particular trim not seen in academic robes. Certainly, the Arabic world was more educated and advanced than the European during the Middle-Ages, but the robes are a coincidence.
[1] https://en.wikipedia.org/wiki/Academic_dress#Overview_and_hi...
[2] https://en.wikipedia.org/wiki/Academic_dress#United_Kingdom_...