I think a big problem is that a lot of things that used to process information just don't exist anymore.
20 years ago, you could have had a CD player, a carrousel CD player, Laserdisc player, VCR, equalizer, Dolby decoder, tape deck, reel to reel deck, record player, receiver, pre-amp, etc, all potential junk.
Now all that is gone and replaced by a computer. The people who cling to the old-school junk are very likely to be able to repair it and therefore won't junk it.
The only junk you are likely to find curbside are major "white goods", and flat screen TVs. At the same time, parts have gotten cheap and powerful microcontrollers are cheap.
What's the motivation for hauling broken crap home? Pretty much the only broken crap that you might find is TVs, and there's not much you can do with the parts in there, or you can sell them after you've repaired them. Good luck with that...