For lack of a better analogy, I think that young Americans with smartphones have embraced a sort of unix philosophy with regards to their social networking, which is to say, they want a service that does one thing and does it well.
They have linkedin profiles for humblebragging about their long term professional life. They have facebook for humblebragging about their long term personal aspirations and achievements. They have twitter for sharing unnoteworthy small thoughts. They have instagram for sharing noteworthy moments that aren't necessarily major life events, and they have snapchat for showing what they're doing right now.
They really don't want something that merges these in any way. The reason being, for any given user publishing content on any of these networks, they all are publishing to different audiences. I want my parents to see my linkedin and to see my facebook. I don't want them to see my twitter necessarily. I don't want them to see my snapchat. (FWIW, in reality I don't have facebook, twitter, linkedin, or snapchat, but this is just an example of how 18-24 y/os think.)
Google had a fix for the issue of audience with g+ and circles, but they fell short on implementation, I think. There weren't enough different ways to share content and shape your profile, pretty much just posts. If they had made better ways to publish temporary posts, static info (like resume and work experience), and to organize views of the site by circles rather than merging them all together, I think they'd have succeeded.
The idea that snapchat can pivot to be anything other than an extension on MMS is ridiculous to me. (It doesn't even do that now, by the way. No group snapchats. The stupid filters like speed you're traveling and the current time look absolutely terrible.)
I think users of snapchat like it for what it is, quick pictures shared to a few people that you think might enjoy it. Nothing you want permanently on the web. Maybe it can become something like periscope or meerkat. I think there's also a market for advertising in the 'featured stories' part of the app, and from the article, it sounds like where they're headed.
But their moves like snapcash, and any aspirations that are separate from sharing temporary moments? Completely bewildering to me. I fear they're trying to become something their users don't want snapchat to be.
One thing I will say, Spiegel seems like a really cool guy with a heart in the right place and is probably a genius. I will not be surprised to see him completely prove me wrong.