Yeah, I can remember when I had trouble believing I was living in the nineties-- surely they were flimsy imaginary years, not years which could be part of the real world.

The Door into Summer is probably the best sf novel for predicting devices, and it's got my favorite piece of general prediction. When the main character wakes up in the future, he doesn't have any way to guess what many of the job descriptions refer to.

I don't know what you mean by vulgar hedonism. To my mind, both the toys and the food have been improving, and I'm glad of it. Low end art is pretty awful, but the world may have always been like that. There's still high end art being made, both popular and fringe. There's more permission to portray sex and violence, but less permission to engage in casual bigotry. I'm not sure this is a change for the worse. (Strange but true: sf fans, at least seem most likely to skim sex scenes, action scenes, and description).

As for golden age sf which predicts society going downhill, I recommend PK Dick, and especially Kornbluth.

I do think things are going wrong, but I don't think lassitude is a good explanation. Instead it's energetic people who've found ways to skim value without doing anything useful.