The social pressures are still there. My social feeds aren't crammed with pictures of food, because I will hide, unfollow, unfriend, etc. anyone who does such stupid crap if they don't respond to a gentle request asking them to stop.

Are social networks enabling this bad behavior to a greater extent than before? I doubt it.

The threads here seem to be a combination of uninformed, speculative, and pointless. The irony of engaging in shallow internet discussion to complain about people using the internet for shallow activities appears to be lost on basically everybody.