​A little strange statement... student did not have to buy it and Universities got it for $100 tape copying fee ( and were free to do with it at they wanted - i.e. "dead-fish license").  FYI: CMU made us sign a document of some type stating it was AT&T's IP to take the undergrad OS course in 1976, but they certainly did not try to keep the code under lock and key with a guard on the door.  Also, the whole idea of the 1956 AT&T consent decree was that AT&T >>had<< to make the IP available -- by law (so they did - which is why they later lost the BSDi/UCB case).   They were given a monopoly if the world access to their patents.

Also by the late 1980s, early 1990's - i.e. Linus' time for early Linux, most Universities world wide were using Vaxen and Sun systems.   On the Vaxen, then tended to have BSD which is what the 386 code was based.   To get a copy of it you needed a BSD license and almost all Universities had them by that point in the USA and the EU.   Hey were were having USENIX conferences hosted in the the EU pretty regularly, and lots of development.

Your comment about not being "forthcoming" I get, as people that power often take a conservative approach if they are not sure.   But the US Gov's deal with AT&T was certainly not supposed to have been that way.