...the rise of the singular "they" should not be condemned, it should be embraced. When professors look down their noses at students they see as poorly trained they are ignoring the fact that these students (and the fluid qualities of language) have effectively solved the problem of awkward “s/he” constructions .Respectfully, I think he's wrong. First, there are other more elegant ways around the problem of gender in English besides ignoring number. Second, if my students want to flaunt the rules of grammar, they need to prove first that they actually know that they are breaking the rules. I don't believe that they know the rules to begin with. When a student writes a grammatically perfect paper for me, s/he can do whatever the hell s/he wants for the rest of their tenure as my student, no questions asked. So far, no one has come remotely close to that.
In general, I understand that our lives are becoming increasingly casual, and I don't think that is necessarily bad. However, it comes with costs. I've written before about how education--and higher education in particular--is in part about distinction, about demarcating some from others on the basis of a given measure (even if that measure is relatively arbitrary). I am all for having a discussion about the appropriateness of this endeavor, but abandoning such distinction is about as radical as it gets, and I don't see it happening any time soon. So, if we're going to distinguish, we need ways to do that. Language is one such way. Not only that, but it's a good way to do it that forces students to wrestle with the (literally) symbolic issues that we find so important sociologically.