The quality of content on Steam is only one of three things current gaming shares with the crash in the 80s.
1, Huge drop in quality with broken and barely functional games, with shit games from big and small publishers alike its easy to spend money on something you wished you hadn't.
2, Gaming machine spam, loads of rubbish consoles with no real market but companies are eager to cash in. See the amount of over priced Android consoles from loads of companies, including Madcatz and Amazon as well as the Ouya. The average consumer didn't really know where to spend money, there are loads of devices aimed at gaming from gaming tablets and handhelds to Android consoles, PCs and the offerings from Nintendo, Sony and Microsoft. The market is hugely diluted at the moment
3, Ever growing tide of consumer dissatisfaction, it mainly started against big publishers like EA and Activision but with dozens of incompetent small developers and publishers trying to chase dollar signs this is rapidly spreading to the once darling child of indie gaming.
Now I am not claiming there will be a crash at all just saying those three things where among the main causes of the big crash.