This year only half the doctoral thesis written in the University of Santiago de Compostela were in English.
42 of these were in Galician, which might make sense considering 44 of these thesis were written by Spanish students working in the fields of arts and humanities, thus they might have written stuff about Galician literature in Galician.
This fact to me highlights the poor aperture of Spanish academics to the outside world and plummets the value of their work.
Some time ago, I was talking with a professor about a possible collaboration and he sent me a PhD thesis of one of his students to give me an overview of what they've been doing. This thesis was in Spanish, I didn't even read it. I believe that if you feel you've done a good work you'll try to share it with other people as much as possible, publishing a thesis in Spanish makes me think you do not value your work enough to make it accessible to other researchers.
I'm disappointed by the Spanish researchers because of this.
Indeed, lots of good researchers are Spanish and I've read plenty of good articles with Spanish authors; however, I believe that this kinds of things lowers the value of their research.