There are places where this sort of push is, manipulative. See the gaming industry where people are in it for "passion".
But no one in dot com or startup or IPO land worked the 60 hour weeks for no reason. They worked them to get paid, and for their lottery tickets / stock options. It was gambling with time.
And for a lot of people that worked out very well. For those that it didnt work out for they still did really well.
If you want a 40 hour a week, no hustle job, then engineering / programing / startups might not be the right choice for you. Your pay will be reflected in that choice.
It has always been this way, it will always be this way: it is a game of sharks and minnows.
Something I try to remember whenever the urge to "hustle" comes back: taking payoff I got from years of startup work, subtracting taxes and spread across those years... Still put me at just above market rate for those years. But instead of that market rate for 40 hour weeks, it was that rate for 80, 100, 120 hour weeks. I could've been working two bog-standard jobs for normal companies, worked fewer hours, and come out ahead.
Everyone has a reason for gambling. It's rarely ever a good reason. But man, it's easy to lose yourself in rationalizations when you're in its thrall...
I do think you are right about the rest as it applies to Twitter and Facebook.
There's been an awful lot written about all of this over the years, much of it overly simplistic and some of it just straight-up wrong; we all want to believe that we're just plain smarter than the ancients, even when those ancients were us.
If you're interested in (ahem) digging into this, start by searching for things like "Digg voting network".