The difference, of course, being that university students in the 1970s stood a good chance of being drafted, and therefore had a direct material interest in opposing the Vietnam war, because the war’s continuation could very well get them killed.
These students, by contrast, are taking a conflict that fundamentally isn’t about them and doesn’t involve them (with the exception of Palestinian-Americans and others with familial relationships in the conflict area), and using it as an excuse to play-act their revolutionary fantasies in a setting they know they’re safe to do so in, secure in the knowledge that push won’t come to shove in the form of something like a draft.
It’s also worth pointing out that the Vietnam protests could legitimately be described as anti-war. Judging by the tenor of these particular protests (and rhetorically analyzing the content of chants, posters, signs, etc.), this round of protest could, at best, be described as a mixed bag: in a “some of them are anti-war, for sure, but a non-insignificant number of them are really just fine with war, they’re only upset their side isn’t winning” way.