I think what your_mind_aches is saying is that the mindset has changed. People who didn't know the internet before social media are more emotionally attached to having one single identity online. Even if in the case of reddit it's not necessarily linked to your real world identity.
It kinda worked for a very long time. Like a good 8-10 years. Sure, there was a slow decline but reddit was still pretty good up until new reddit was introduced.
I remember being embarrassed to discuss reddit irl in a way that I wasn't embarrassed to discuss Facebook, for example. Reddit was the dirty little secret.