Sure, in that very specific and somewhat unlikely scenario. Maybe the professor demanded a handjob as well. Or perhaps the university claims ownership over all

Sure, in that very specific and somewhat unlikely scenario. Maybe the professor demanded a handjob as well. Or perhaps the university claims ownership over all intellectual property produced by the PhD student as part of their thesis, and they're unable to upstream their source to any project under any license. In any case, it sounds like you want to blame the llvm license for the bad feelings the student might have, but that blame is misdirected: the student should aim their anger (if any) at their professor or university for introducing unreasonable requirements. Or maybe they should suck it up because without llvm they would have had to pick another subject for their thesis. I suspect that llvm wouldn't have grown to where it is now (for better or for worse) with a copyleft license. And then our student would have been "forced" to contribute to gcc instead, and sign over their copyright to the fsf instead. Finally I think the academic world is a lot like permissive licenses already. Anyone can read papers, use that information in any way, and there is no obligation to contribute back. Only when writing new papers are you expected to acknowledge your sources.