Your question (the post follows) about why we don’t teach voseo in textbooks falls in the realm of sociolinguistics. I assume you mean U.S. textbooks and we have to ask who writes them and under what conditions. Most textbooks come out of a tradition e.g. our U.S. history books were written for decades by White Virginians and other Southern historians b/c history was a gentleman’s pursuit. Their slant on Southern history colored (play on words there) our view of our own history, taking the color out of it, so to speak, so for the last few decades we have been trying to catch up and correct that slant.
I would say that voseo is generally associated with less educated speakers and the traditional class in foreign language study was directed toward gentlemen and ladies who would be associating with people of their own class. I know that that sounds horribly archaic nowadays, but I have fl textbooks from the earlier part of the last century that contain passages just like that.
Even now, I suspect there are teachers from Latin America who would object to introducing speech that in their country is derided as lower class, no matter how wide-spread, even among the upper classes, it may be.
I’m not advocating any approach; my students had trouble with tu and usted, forget vosotros and vos.
I look forward to seeing the responses to your very interesting question.
Thanks for the many replies to my question about the use of “vosotros”.
It seems that most of you feel that we should include it in our teaching. Why
then, do we not include the voseo (which I personally use) when it is used in
many countries? And should we include it? Most texts will only mention it in
passing and not until levels 3 or 4. Thoughts?